Microsoft assesses that credentials acquired from CovertNetwork-1658 password spray operations are used by multiple Chinese threat actors. In particular, Microsoft has observed the Chinese threat actor Storm-0940 using credentials from CovertNetwork-1658. Active since at least 2021, Storm-0940 obtains initial access through password spray and brute-force attacks, or by exploiting or misusing network edge applications and services. Storm-0940 is known to target organizations in North America and Europe, including think tanks, government organizations, non-governmental organizations, law firms, defense industrial base, and others.

As with any observed nation-state threat actor activity, Microsoft has directly notified targeted or compromised customers, providing them with important information needed to help secure their environments. In this blog, we provide more information about CovertNetwork-1658 infrastructure, and associated Storm-0940 activity. We also share mitigation recommendations, detection information, and hunting queries that can help organizations identify, investigate, and mitigate associated activity.

What is CovertNetwork-1658?

Microsoft tracks a network of compromised small office and home office (SOHO) routers as CovertNetwork-1658. SOHO routers manufactured by TP-Link make up most of this network. Microsoft uses “CovertNetwork” to refer to a collection of egress IPs consisting of compromised or leased devices that may be used by one or more threat actors.

CovertNetwork-1658 specifically refers to a collection of egress IPs that may be used by one or more Chinese threat actors and is wholly comprised of compromised devices. Microsoft assesses that a threat actor located in China established and maintains this network. The threat actor exploits a vulnerability in the routers to gain remote code execution capability. We continue to investigate the specific exploit by which this threat actor compromises these routers. Microsoft assesses that multiple Chinese threat actors use the credentials acquired from CovertNetwork-1658 password spray operations to perform computer network exploitation (CNE) activities.

Post-compromise activity on compromised routers

After successfully gaining access to a vulnerable router, in some instances, the following steps are taken by the threat actor to prepare the router for password spray operations:

1. Download Telnet binary from a remote File Transfer Protocol (FTP) server
2. Download xlogin backdoor binary from a remote FTP server
3. Utilize the downloaded Telnet and xlogin binaries to start an access-controlled command shell on TCP port 7777
4. Connect and authenticate to the xlogin backdoor listening on TCP port 7777
5. Download a SOCKS5 server binary to router
6. Start SOCKS5 server on TCP port 11288

CovertNetwork-1658 is observed conducting their password spray campaigns through this proxy network to ensure the password spray attempts originate from the compromised devices.

Password spray activity from CovertNetwork-1658 infrastructure

Microsoft has observed multiple password spray campaigns originating from CovertNetwork-1658 infrastructure. In these campaigns, CovertNetwork-1658 submits a very small number of sign-in attempts to many accounts at a target organization. In about 80 percent of cases, CovertNetwork-1658 makes only one sign-in attempt per account per day. Figure 2 depicts this distribution in greater detail.

CovertNetwork-1658 infrastructure is difficult to monitor due to the following characteristics:

• The use of compromised SOHO IP addresses
• The use of a rotating set of IP addresses at any given time. The threat actors had thousands of available IP addresses at their disposal. The average uptime for a CovertNetwork-1658 node is approximately 90 days.
• The low-volume password spray process; for example, monitoring for multiple failed sign-in attempts from one IP address or to one account will not detect this activity

Various security vendors have reported on CovertNetwork-1658 activities, including Sekoia (July 2024) and Team Cymru (August 2024). Microsoft assesses that after these blogs were published, the usage of CovertNetwork-1658 network has declined substantially. The below chart highlights a steady and steep decline in the use of CovertNetwork-1658’s original infrastructure since their activities have been exposed in public reporting as observed in Censys.IO data.

Microsoft assesses that CovertNetwork-1658 has not stopped operations as indicated in recent activity but is likely acquiring new infrastructure with modified fingerprints from what has been publicly disclosed. An observed increase in recent activity may be early evidence supporting this assessment.

Historically, Microsoft has observed an average of 8,000 compromised devices actively engaged in the CovertNetwork-1658 network at any given time. On average, about 20 percent of these devices perform password spraying at any given time. Any threat actor using the CovertNetwork-1658 infrastructure could conduct password spraying campaigns at a larger scale and greatly increase the likelihood of successful credential compromise and initial access to multiple organizations in a short amount of time. This scale, combined with quick operational turnover of compromised credentials between CovertNetwork-1658 and Chinese threat actors, allows for the potential of account compromises across multiple sectors and geographic regions.

Below are User Agent Strings* observed in the password spray activity:

• Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko
• Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36

*Note: We updated this list of User Agent Strings on November 4, 2024 to fix typos.

Observed activity tied to Storm-0940

Microsoft has observed numerous cases where Storm-0940 has gained initial access to target organizations using valid credentials obtained through CovertNetwork-1658’s password spray operations. In some instances, Storm-0940 was observed using compromised credentials that were obtained from CovertNetwork-1658 infrastructure on the same day. This quick operational hand-off of compromised credentials is evidence of a likely close working relationship between the operators of CovertNetwork-1658 and Storm-0940.

After successfully gaining access to a victim environment, in some instances, Storm-0940 has been observed:        

• Using scanning and credential dumping tools to move laterally within the network;
• Attempting to access network devices and install proxy tools and remote access trojans (RATs) for persistence; and
• Attempting to exfiltrate data.

Recommendations

Organizations can defend against password spraying by building credential hygiene and hardening cloud identities. Microsoft recommends the following mitigations to reduce the impact of this threat:

• Educate users on the importance of credential hygiene and avoiding password reuse.
• Enforce multi-factor authentication (MFA) on all accounts, remove users excluded from MFA, and strictly require MFA from all devices, in all locations, at all times. Microsoft continues to expand MFA defaults for products and services like Azure to broaden MFA adoption.
  • Consider transitioning to a passwordless primary authentication method, such as Azure MFA, certificates, or Windows Hello for Business.
  • Secure Remote Desktop Protocol (RDP) or Windows Virtual Desktop endpoints with MFA to harden against password spray or brute force attacks.
• Enable passwordless authentication methods (for example, Windows Hello, FIDO keys, or Microsoft Authenticator) for accounts that support passwordless. For accounts that still require passwords, use authenticator apps like Microsoft Authenticator for MFA.
• Disable legacy authentication.
• Use a cloud-based identity security solution to identify and detect threats or compromised identities.
• Disable stale or unused accounts.
• Reset account passwords for any accounts targeted during a password spray attack. If a targeted account had system-level permissions, further investigation may be warranted.
• Implement the Azure Security Benchmark and general best practices for securing identity infrastructure, including:
  • Create conditional access policies to allow or disallow access to the environment based on defined criteria.
• • Block legacy authentication with Azure AD by using Conditional Access. Legacy authentication protocols don’t have the ability to enforce MFA, so blocking such authentication methods will prevent password spray attackers from taking advantage of the lack of MFA on those protocols.
  • Enable AD FS web application proxy extranet lockout to protect users from potential password brute force compromise.
• Secure accounts with credential hygiene:
  • Practice the principle of least privilege and audit privileged account activity in your Azure AD environments to slow and stop attackers.
  • Deploy Azure AD Connect Health for ADFS. This captures failed attempts as well as IP addresses recorded in ADFS logs for bad requests via the Risky IP report.
  • Use Azure AD password protection to detect and block known weak passwords and their variants.
  • Turn on identity protection in Azure AD to monitor for identity-based risks and create policies for risky sign ins.
• Educate users about phishing attempts and MFA fatigue attacks. Encourage users to report unsolicited MFA authentication prompts.
• Review your Anomaly detection policies in Defender for Cloud Apps under Microsoft 365 Defender Policies by going to Cloud Apps > Policies > Policy management. Then select Anomaly detection policy.

Detection details

Alerts with the following titles in the Security Center can indicate threat activity on your network:

Microsoft Defender for Endpoint

The following Microsoft Defender for Endpoint alert can indicate associated threat activity:

• Storm-0940 actor activity detected

Microsoft Defender XDR

The following alert might indicate threat activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Password spray attacks originating from single ISP

Microsoft Defender for Identity

The following Microsoft Defender for Identity alerts can indicate associated threat activity:

• Password Spray
• Unfamiliar Sign-in properties
• Atypical travel
• Suspicious behavior: Impossible travel activity

Microsoft Defender for Cloud Apps

The following Microsoft Defender for Cloud Apps alerts can indicate associated threat activity:

• Suspicious Administrative Activity
• Impossible travel activity

Hunting queries

Microsoft Defender XDR

Microsoft Defender XDR customers can run the following query to find related activity in their networks:

Potential Storm-0940 activity           

This query identifies UserAgents obtained from observed activity and AAD SignInEvent attributes that identify potential activity to guide investigation:

//Advanced Hunting Query
let suspAppRes = datatable(appId:string, resourceId:string)
[
    "1950a258-227b-4e31-a9cf-717495945fc2", "00000003-0000-0000-c000-000000000000"
];
let userAgents = datatable(userAgent:string)
[
    "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko",
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36" //Low fidelity
];
AADSignInEventsBeta
| where Timestamp >=ago(30d)
| where ApplicationId in ((suspAppRes | project appId)) and ResourceId in ((suspAppRes | project resourceId)) and UserAgent in ((userAgents| project userAgent))
Failed sign-in activity
The following query identifies failed attempts to sign-in from multiple sources that originate from a single ISP. Attackers distribute attacks from multiple IP addresses across a single service provider to evade detection
IdentityLogonEvents
| where Timestamp > ago(4h)
| where ActionType == "LogonFailed"
| where isnotempty(AccountObjectId)
| summarize TargetCount = dcount(AccountObjectId), TargetCountry = dcount(Location), TargetIPAddress = dcount(IPAddress) by ISP
| where TargetCount >= 100
| where TargetCountry >= 5
| where TargetIPAddress >= 25

Microsoft Sentinel

Microsoft Sentinel customers can use the TI Mapping analytics (a series of analytics all prefixed with ‘TI map’) to automatically match the malicious domain indicators mentioned in this blog post with data in their workspace. If the TI Map analytics are not currently deployed, customers can install the Threat Intelligence solution from the Microsoft Sentinel Content Hub to have the analytics rule deployed in their Sentinel workspace. More details on the Content Hub can be found here: https://learn.microsoft.com/azure/sentinel/sentinel-solutions-deploy.

Potential Storm-0940 activity

This query identifies UserAgents obtained from observed activity and AAD SignInEvent attributes that identify potential activity to guide investigation:

//sentinelquery
let suspAppRes = datatable(appId:string, resourceId:string)
[
    "1950a258-227b-4e31-a9cf-717495945fc2", "00000003-0000-0000-c000-000000000000"
];
let userAgents = datatable(userAgent:string)
[
    "Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko",
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Safari/537.36" //Low fidelity
];
SigninLogs
| where TimeGenerated >=ago(30d)
| where AppId  in ((suspAppRes | project appId)) and ResourceIdentity in ((suspAppRes | project resourceId)) and UserAgent in ((userAgents| project userAgent))

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn at https://www.linkedin.com/showcase/microsoft-threat-intelligence, and on X (formerly Twitter) at https://twitter.com/MsftSecIntel.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast: https://thecyberwire.com/podcasts/microsoft-threat-intelligence.

The post Chinese threat actor Storm-0940 uses credentials from password spray attacks from a covert network appeared first on Microsoft Security Blog.

Storm-0501 has been active as early as 2021, initially observed deploying the Sabbath(54bb47h) ransomware in attacks targeting US school districts, publicly leaking data for extortion, and even directly messaging school staff and parents. Since then, most of the threat actor’s attacks have been opportunistic, as the group began operating as a ransomware-as-a-service (RaaS) affiliate deploying multiple ransomware payloads developed and maintained by other threat actors over the years, including Hive, BlackCat (ALPHV), Hunters International, LockBit, and most recently, Embargo ransomware. The threat actor was also recently observed targeting hospitals in the US.

Storm-0501 is the latest threat actor observed to exploit weak credentials and over-privileged accounts to move from organizations’ on-premises environment to cloud environments. They stole credentials and used them to gain control of the network, eventually creating persistent backdoor access to the cloud environment and deploying ransomware to the on-premises. Microsoft previously observed threat actors such as Octo Tempest and Manatee Tempest targeting both on-premises and cloud environments and exploiting the interfaces between the environments to achieve their goals.

As hybrid cloud environments become more prevalent, the challenge of securing resources across multiple platforms grows ever more critical for organizations. Microsoft is committed to helping customers understand these attacks and build effective defenses against them.

In this blog post, we will go over Storm-0501’s tactics, techniques, and procedures (TTPs), typical attack methods, and expansion to the cloud. We will also provide information on how Microsoft detects activities related to this kind of attack, as well as provide mitigation guidance to help defenders protect their environment.

Analysis of the recent Storm-0501 campaign

On-premises compromise

Initial access and reconnaissance

Storm-0501 previously achieved initial access through intrusions facilitated by access brokers like Storm-0249 and Storm-0900, leveraging possibly stolen compromised credentials to sign in to the target system, or exploiting various known remote code execution vulnerabilities in unpatched public-facing servers. In a recent campaign, Storm-0501 exploited known vulnerabilities in Zoho ManageEngine (CVE-2022-47966), Citrix NetScaler (CVE-2023-4966), and ColdFusion 2016 application (possibly CVE-2023-29300 or CVE-2023-38203). In cases observed by Microsoft, these initial access techniques, combined with insufficient operational security practices by the targets, provided the threat actor with administrative privileges on the target device.

After gaining initial access and code execution capabilities on the affected device in the network, the threat actor performed extensive discovery to find potential desirable targets such as high-value assets and general domain information like Domain Administrator users and domain forest trust. Common native Windows tools and commands, such as systeminfo.exe, net.exe, nltest.exe, tasklist.exe, were leveraged in this phase. The threat actor also utilized open-source tools like ossec-win32 and OSQuery to query additional endpoint information. Additionally, in some of the attacks, we observed the threat actor running an obfuscated version of ADRecon.ps1 called obfs.ps1 or recon.ps1 for Active Directory reconnaissance.

Following initial access and reconnaissance, the threat actor deployed several remote monitoring and management tools (RMMs), such as Level.io, AnyDesk, and NinjaOne to interact with the compromised device and maintain persistence.

Credential access and lateral movement

The threat actor took advantage of admin privileges on the local devices it compromised during initial access and attempted to gain access to more accounts within the network through several methods. The threat actor primarily utilized Impacket’s SecretsDump module, which extracts credentials over the network, and leveraged it across an extensive number of devices to obtain credentials. The threat actor used the compromised credentials to access more devices in the network and then leveraged Impacket again to collect additional credentials. The threat actor then repeated this process until they compromised a large set of credentials that potentially included multiple Domain Admin credentials.

In addition, the threat actor was observed attempting to gather secrets by reading sensitive files and in some cases gathering KeePass secrets from the compromised devices. The threat actor used EncryptedStore’s Find-KeePassConfig.ps1 PowerShell script to output the database location and keyfile/user master key information and launch the KeePass executable to gather the credentials. We assess with medium confidence that the threat actor also performed extensive brute force activity on a few occasions to gain additional credentials for specific accounts.

The threat actor was observed leveraging Cobalt Strike to move laterally across the network using the compromised credentials and using the tool’s command-and-control (C2) capabilities to directly communicate with the endpoints and send further commands. The common Cobalt Strike Beacon file types used in these campaigns were .dll files and .ocx files that were launched by rundll32.exe and regsvr32.exe respectively. Moreover, the “license_id” associated with this Cobalt Strike Beacon is “666”.  The “license_id” definition is commonly referred to as Watermark and is a nine-digit value that is unique per legitimate license provided by Cobalt Strike. In this case, the “license_id” was modified with 3-digit unique value in all the beacon configurations.

In cases we observed, the threat actor’s lateral movement across the campaign ended with a Domain Admin compromise and access to a Domain Controller that eventually enabled them to deploy ransomware across the devices in the network.

Data collection and exfiltration

The threat actor was observed exfiltrating sensitive data from compromised devices. To exfiltrate data, the threat actor used the open-source tool Rclone and renamed it to known Windows binary names or variations of them, such as svhost.exe or scvhost.exe as masquerading means. The threat actor employed the renamed Rclone binaries to transfer data to the cloud, using a dedicated configuration that synchronized files to public cloud storage services such as MegaSync across multiple threads. The following are command line examples used by the threat actor in demonstrating this behavior:

• Svhost.exe copy –filter-from [REDACTED] [REDACTED] config:[REDACTED] -q –ignore-existing –auto-confirm –multi-thread-streams 11 –transfers 11
• scvhost.exe –config C:\Windows\Debug\a.conf copy [REDACTED UNC PATH] [REDACTED]

Defense evasion

The threat actor attempted to evade detection by tampering with security products in some of the devices they got hands-on-keyboard access to. They employed an open-source tool, resorted to PowerShell cmdlets and existing binaries to evade detection, and in some cases, distributed Group Policy Object (GPO) policies to tamper with security products.

On-premises to cloud pivot

In their recent campaign, we noticed a shift in Storm-0501’s methods. The threat actor used the credentials, specifically Microsoft Entra ID (formerly Azure AD), that were stolen from earlier in the attack to move laterally from the on-premises to the cloud environment and establish persistent access to the target network through a backdoor.

Storm-0501 was observed using the following attack vectors and pivot points on the on-premises side to gain subsequent control in Microsoft Entra ID:

Microsoft Entra Connect Sync account compromise

Microsoft Entra Connect, previously known as Azure AD Connect, is an on-premises Microsoft application that plays a critical role in synchronizing passwords and sensitive data between Active Directory (AD) objects and Microsoft Entra ID objects. Microsoft Entra Connect synchronizes the on-premises identity and Microsoft Entra identity of a user account to allow the user to sign in to both realms with the same password. To deploy Microsoft Entra Connect, the application must be installed on an on-premises server or an Azure VM. To decrease the attack surface, Microsoft recommends that organizations deploy Microsoft Entra Connect on a domain-joined server and restrict administrative access to domain administrators or other tightly controlled security groups. Microsoft Incident Response also published recommendations on preventing cloud identity compromise.

Microsoft Entra Connect Sync is a component of Microsoft Entra Connect that synchronizes identity data between on-premises environments and Microsoft Entra ID. During the Microsoft Entra Connect installation process, at least two new accounts (more accounts are created if there are multiple forests) responsible for the synchronization are created, one in the on-premises AD realm and the other in the Microsoft Entra ID tenant. These service accounts are responsible for the synchronization process.

The on-premises account name is prefixed with “MSOL_” and has permissions to replicate directory changes, modify passwords, modify users, modify groups, and more (see full permissions here).

The cloud Microsoft Entra ID account is prefixed with “sync_<Entra Connect server name>_” and has the account display name set to “On-Premises Directory Synchronization Service Account”. This user account is assigned with the Directory Synchronization Accounts role (see detailed permissions of this role here). Microsoft recently implemented a change in Microsoft Entra ID that restricts permissions on the Directory Synchronization Accounts (DSA) role in Microsoft Entra Connect Sync and Microsoft Entra Cloud Sync and helps prevent abuse.

The on-premises and cloud service accounts conduct the syncing operation every few minutes, similar to Password Hash Synchronization (PHS), to uphold real time user experience. Both user accounts mentioned above are crucial for the Microsoft Entra Connect Sync service operations and their credentials are saved encrypted via DPAPI (Data Protection API) on the server’s disk or a remote SQL server.

We can assess with high confidence that in the recent Storm-0501 campaign, the threat actor specifically located Microsoft Entra Connect Sync servers and managed to extract the plain text credentials of the Microsoft Entra Connect cloud and on-premises sync accounts. We assess that the threat actor was able to achieve this because of the previous malicious activities described in this blog post, such as using Impacket to steal credentials and DPAPI encryption keys, and tampering with security products.

Following the compromise of the cloud Directory Synchronization Account, the threat actor can authenticate using the clear text credentials and get an access token to Microsoft Graph. The compromise of the Microsoft Entra Connect Sync account presents a high risk to the target, as it can allow the threat actor to set or change Microsoft Entra ID passwords of any hybrid account (on-premises account that is synced to Microsoft Entra ID).

Cloud session hijacking of on-premises user account

Another way to pivot from on-premises to Microsoft Entra ID is to gain control of an on-premises user account that has a respective user account in the cloud. In some of the Storm-0501 cases we investigated, at least one of the Domain Admin accounts that was compromised had a respective account in Microsoft Entra ID, with multifactor authentication (MFA) disabled, and assigned with a Global Administrator role. It is important to mention that the sync service is unavailable for administrative accounts in Microsoft Entra, hence the passwords and other data are not synced from the on-premises account to the Microsoft Entra account in this case. However, if the passwords for both accounts are the same, or obtainable by on-premises credential theft techniques (i.e. web browsers passwords store), then the pivot is possible.

If a compromised on-premises user account is not assigned with an administrative role in Microsoft Entra ID and is synced to the cloud and no security boundaries such as MFA or Conditional Access are set, then the threat actor could escalate to the cloud through the following:

1. If the password is known, then logging in to Microsoft Entra is possible from any device.
2. If the password is unknown, the threat actor can reset the on-premises user password, and after a few minutes the new password will be synced to the cloud.
3. If they hold credentials of a compromised Microsoft Entra Directory Synchronization Account, they can set the cloud password using AADInternals’ Set-AADIntUserPassword cmdlet.

If MFA for that user account is enabled, then authentication with the user will require the threat actor to tamper with the MFA or gain control of a device owned by the user and subsequently hijack its cloud session or extract its Microsoft Entra access tokens along with their MFA claims.

MFA is a security practice that requires users to provide two or more verification factors to gain access to a resource and is a recommended security practice for all users, especially for privileged administrators. A lack of MFA or Conditional Access policies limiting the sign-in options opens a wide door of possibilities for the attacker to pivot to the cloud environment, especially if the user has administrative privileges. To increase the security of admin accounts, Microsoft is rolling out additional tenant-level security measures to require MFA for all Azure users.

Impact

Cloud compromise leading to backdoor

Following a successful pivot from the on-premises environment to the cloud through the compromised Microsoft Entra Connect Sync user account or the cloud admin account compromised through cloud session hijacking, the threat actor was able to connect to Microsoft Entra (portal/MS Graph) from any device, using a privileged Microsoft Entra ID account, such as a Global Administrator, and was no longer limited to the compromised devices.

Once Global Administrator access is available for Storm-0501, we observed them creating a persistent backdoor access for later use by creating a new federated domain in the tenant. This backdoor enables an attacker to sign in as any user of the Microsoft Entra ID tenant in hand if the Microsoft Entra ID user property ImmutableId is known or set by the attackers. For users that are configured to be synced by the Microsoft Entra Connect service, the ImmutableId property is automatically populated, while for users that are not synced the default value is null. However, users with administrative privileges can add an ImmutableId value, regardless.

The threat actor used the open-source tool AADInternals, and its Microsoft Entra ID capabilities to create the backdoor. AADInternals is a PowerShell module designed for security researchers and penetration testers that provides various methods for interacting and testing Microsoft Entra ID and is commonly used by Storm-0501. To create the backdoor, the threat actor first needed to have a domain of their own that is registered to Microsoft Entra ID. The attacker’s next step is to determine whether the target domain is managed or federated. A federated domain in Microsoft Entra ID is a domain that is configured to use federation technologies, such as Active Directory Federation Services (AD FS), to authenticate users. If the target domain is managed, then the attackers need to convert it to a federated one and provide a root certificate to sign future tokens upon user authentication and authorization processes. If the target domain is already federated, then the attackers need to add the root certificate as “NextSigningCertificate”.

Once a backdoor domain is available for use, the threat actor creates a federation trust between the compromised tenant, and their own tenant. The threat actor uses the AADInternals commands that enable the creation of Security Assertion Markup Language (SAML or SAML2) tokens, which can be used to impersonate any user in the organization and bypass MFA to sign in to any application. Microsoft observed the actor using the SAML token sign in to Office 365.

On-premises compromise leading to ransomware

Once the threat actor achieved sufficient control over the network, successfully extracted sensitive files, and managed to move laterally to the cloud environment, the threat actor then deployed the Embargo ransomware across the organization. We observed that the threat actor did not always resort to ransomware distribution, and in some cases only maintained backdoor access to the network.

Embargo ransomware is a new strain developed in Rust, known to use advanced encryption methods. Operating under the RaaS model, the ransomware group behind Embargo allows affiliates like Storm-0501 to use its platform to launch attacks in exchange for a share of the ransom. Embargo affiliates employ double extortion tactics, where they first encrypt a victim’s files and threaten to leak stolen sensitive data unless a ransom is paid.

In the cases observed by Microsoft, the threat actor leveraged compromised Domain Admin accounts to distribute the Embargo ransomware via a scheduled task named “SysUpdate” that was registered via GPO on the devices in the network. The ransomware binaries names that were used were PostalScanImporter.exe and win.exe. Once the files on the target devices were encrypted, the encrypted files extension changed to .partial, .564ba1, and .embargo.

Mitigation and protection guidance

Microsoft recently implemented a change in Microsoft Entra ID that restricts permissions on the Directory Synchronization Accounts (DSA) role in Microsoft Entra Connect Sync and Microsoft Entra Cloud Sync as part of ongoing security hardening. This change helps prevent threat actors from abusing Directory Synchronization Accounts in attacks.

Customers may also refer to Microsoft’s human-operated ransomware overview for general hardening recommendations against ransomware attacks.

The other techniques used by threat actors and described in this blog can be mitigated by adopting the following security measures:

• Secure accounts with credential hygiene: practice the principle of least privilege and audit privileged account activity in your Microsoft Entra ID environments to slow and stop attackers.
• Enable Conditional Access policies – Conditional Access policies are evaluated and enforced every time the user attempts to sign in. Organizations can protect themselves from attacks that leverage stolen credentials by enabling policies such as device compliance or trusted IP address requirements.
  • Set a Conditional Access policy to limit the access of Microsoft Entra ID sync accounts from untrusted IP addresses to all cloud apps. The Microsoft Entra ID sync account is identified by having the role ‘Directory Synchronization Accounts’. Please refer to the Advanced Hunting section and check the relevant query to get those IP addresses.
• Implement Conditional Access authentication strength to require phishing-resistant authentication for employees and external users for critical apps.
• Follow Microsoft’s best practices for securing Active Directory Federation Services.  
• Refer to Azure Identity Management and access control security best practices for further steps and recommendations to manage, design, and secure your Azure AD environment can be found by referring.
• Ensure Microsoft Defender for Cloud Apps connectors are turned on for your organization to receive alerts on the Microsoft Entra ID sync account and all other users.
• Enable protection to prevent by-passing of cloud Microsoft Entra MFA when federated with Microsoft Entra ID.
• Set the validatingDomains property of federatedTokenValidationPolicy to “all” to block attempts to sign-in to any non-federated domain (like .onmicrosoft.com) with SAML tokens.
• Turn on Microsoft Entra ID protection to monitor identity-based risks and create risk-based conditional access policies to remediate risky sign-ins.
• Turn on tamper protection features to prevent attackers from stopping security services such as Microsoft Defender for Endpoint, which can help prevent hybrid cloud environment attacks such as Microsoft Entra Connect abuse.
• Refer to the recommendations in our attacker technique profile, including use of Windows Defender Application Control or AppLocker to create policies to block unapproved information technology (IT) management tools to protect against the abuse of legitimate remote management tools like AnyDesk or Level.io.
• Run endpoint detection and response (EDR) in block mode so that Defender for Endpoint can block malicious artifacts, even when your non-Microsoft antivirus does not detect the threat or when Microsoft Defender Antivirus is running in passive mode. EDR in block mode works behind the scenes to remediate malicious artifacts detected post-breach.
• Turn on investigation and remediation in full automated mode to allow Defender for Endpoint to take immediate action on alerts to help remediate alerts, significantly reducing alert volume.

Detection details

Alerts with the following names can be in use when investigating the current campaign of Storm-0501.

Microsoft Defender XDR detections

Microsoft Defender Antivirus 

Microsoft Defender Antivirus detects the Cobalt Strike Beacon as the following:

• Behavior:Win32/CobaltStrike
• Backdoor:Win64/CobaltStrike
• HackTool:Win64/CobaltStrike

Additional Cobalt Strike components are detected as the following:

• TrojanDropper:PowerShell/Cobacis
• Trojan:Win64/TurtleLoader.CS
• Exploit:Win32/ShellCode.BN

Microsoft Defender Antivirus detects tools that enable Microsoft Entra ID enumeration as the following malware: 

• Backdoor:Win32/SuspAadInternalsUsage

Embargo Ransomware threat components are detected as the following:

• Ransom:Win32/Embargo

Microsoft Defender for Endpoint 

Alerts with the following titles in the security center can indicate threat activity related to Storm-0501 on your network:

• Ransomware-linked Storm-0501 threat actor detected

The following alerts might also indicate threat activity associated with this threat. These alerts, however, can be triggered by unrelated threat activity and are not monitored in the status cards provided with this report. 

• Possible Adobe ColdFusion vulnerability exploitation
• Compromised account conducting hands-on-keyboard attack
• Ongoing hands-on-keyboard attacker activity detected (Cobalt Strike)
• Ongoing hands-on-keyboard attack via Impacket toolkit
• Suspicious Microsoft Defender Antivirus exclusion
• Attempt to turn off Microsoft Defender Antivirus protection
• Renaming of legitimate tools for possible data exfiltration
• BlackCat ransomware
• ‘Embargo’ ransomware was detected and was active
• Suspicious Group Policy action detected
• An active ‘Embargo’ ransomware was detected

The following alerts might indicate on-premises to cloud pivot through Microsoft Entra Connect:

• Entra Connect Sync credentials extraction attempt
• Suspicious cmdlets launch using AADInternals
• Potential Entra Connect Tampering
• Indication of local security authority secrets theft

Microsoft Defender for Identity

The following Microsoft Defender for Identity alerts can indicate activity related to this threat:

• Data exfiltration over SMB
• Suspected DCSync attack

Microsoft Defender for Cloud Apps

Microsoft Defender for Cloud Apps can detect abuse of permissions in Microsoft Entra ID and other cloud apps. Activities related to the Storm-0501 campaign described in this blog are detected as the following:

• Backdoor creation using AADInternals tool
• Compromised Microsoft Entra ID Cloud Sync account
• Suspicious sign-in to Microsoft Entra Connect Sync account
• Entra Connect Sync account suspicious activity following a suspicious login
• AADInternals tool used by a Microsoft Entra Sync account
• Suspicious login from AADInternals tool

Microsoft Defender Vulnerability Management

Microsoft Defender Vulnerability Management surfaces devices that may be affected by the following vulnerabilities used in this threat:

• CVE-2022-47966

Threat intelligence reports 

Microsoft customers can use the following reports in Microsoft Defender Threat Intelligence to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection information, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments: 

• Storm-0501

Advanced hunting 

Microsoft Defender XDR

Microsoft Defender XDR customers can run the following query to find related activity in their networks:

Microsoft Entra Connect Sync account exploration

Explore sign-in activity from IdentityLogonEvents, look for uncommon behavior, such as sign-ins from newly seen IP addresses or sign-ins to new applications that are non-sync related.

IdentityLogonEvents
| where Timestamp > ago(30d)
| where AccountDisplayName contains "On-Premises Directory Synchronization Service Account"
| extend ApplicationName = tostring(RawEventData.ApplicationName)
| project-reorder Timestamp, AccountDisplayName, AccountObjectId, IPAddress, ActionType, ApplicationName, OSPlatform, DeviceType

Usually, the activity of the sync account is repetitive, coming from the same IP address to the same application, any deviation from the natural flow is worth investigating. Cloud applications that normally accessed by the Microsoft Entra ID sync account are “Microsoft Azure Active Directory Connect”, “Windows Azure Active Directory”, “Microsoft Online Syndication Partner Portal”

Explore the cloud activity (a.k.a ActionType) of the sync account, same as above, this account by nature performs a certain set of actions including ‘update User.’, ‘update Device.’ and so on. New and uncommon activity from this user might indicate an interactive use of the account, even though it could have been from someone inside the organization it could also be the threat actor.

CloudAppEvents
| where Timestamp > ago(30d)
| where AccountDisplayName has "On-Premises Directory Synchronization Service Account"
| extend Workload = RawEventData.Workload
| project-reorder Timestamp, IPAddress, AccountObjectId, ActionType, Application, Workload, DeviceType, OSPlatform, UserAgent, ISP

Pay close attention to action from different DeviceTypes or OSPlatforms, this account automated service is performed from one specific machine, so there shouldn’t be any variety in these fields.

Check which IP addresses Microsoft Entra Connect Sync account uses

This query reveals all IP addresses that the default Microsoft Entra Connect Sync account uses so those could be added as trusted IP addresses for the Entra ID sync account (make sure the account is not compromised before relying on this list)

IdentityLogonEvents
| where AccountDisplayName has "On-Premises Directory Synchronization Service Account"
| where ActionType == "LogonSuccess"
| distinct IPAddress
| union (CloudAppEvents
| where AccountDisplayName has "On-Premises Directory Synchronization Service Account"
| distinct IPAddress)
| distinct IPAddress

Federation and authentication domain changes

Explore the addition of a new authentication or federation domain, validate that the new domain is valid one and was purposefully added

CloudAppEvents
| where Timestamp > ago(30d)
| where ActionType in ("Set domain authentication.", "Set federation settings on domain.")

Microsoft Sentinel

Microsoft Sentinel customers can use the TI Mapping analytics (a series of analytics all prefixed with ‘TI map’) to automatically match the malicious domain indicators mentioned in this blog post with data in their workspace. If the TI Map analytics are not currently deployed, customers can install the Threat Intelligence solution from the Microsoft Sentinel Content Hub to have the analytics rule deployed in their Sentinel workspace.

Assess your environment for Manage Engine, Netscaler, and ColdFusion vulnerabilities.

DeviceTvmSoftwareVulnerabilities  
| where CveId in ("CVE-2022-47966","CVE-2023-4966","CVE-2023-29300","CVE-2023-38203")   
| project DeviceId,DeviceName,OSPlatform,OSVersion,SoftwareVendor,SoftwareName,SoftwareVersion,  
CveId,VulnerabilitySeverityLevel  
| join kind=inner ( DeviceTvmSoftwareVulnerabilitiesKB | project CveId, CvssScore,IsExploitAvailable,VulnerabilitySeverityLevel,PublishedDate,VulnerabilityDescription,AffectedSoftware ) on CveId  
| project DeviceId,DeviceName,OSPlatform,OSVersion,SoftwareVendor,SoftwareName,SoftwareVersion,  
CveId,VulnerabilitySeverityLevel,CvssScore,IsExploitAvailable,PublishedDate,VulnerabilityDescription,AffectedSoftware

Search for file IOC

let selectedTimestamp = datetime(2024-09-17T00:00:00.0000000Z);
let fileName = dynamic(["PostalScanImporter.exe","win.exe","name.dll","248.dll","cs240.dll","fel.ocx","theme.ocx","hana.ocx","obfs.ps1","recon.ps1"]); 
let FileSHA256 = dynamic(["efb2f6452d7b0a63f6f2f4d8db49433259249df598391dd79f64df1ee3880a8d","a9aeb861817f3e4e74134622cbe298909e28d0fcc1e72f179a32adc637293a40","caa21a8f13a0b77ff5808ad7725ff3af9b74ce5b67426c84538b8fa43820a031","53e2dec3e16a0ff000a8c8c279eeeca8b4437edb8ec8462bfbd9f64ded8072d9","827f7178802b2e92988d7cff349648f334bc86317b0b628f4bb9264285fccf5f","ee80f3e3ad43a283cbc83992e235e4c1b03ff3437c880be02ab1d15d92a8348a","de09ec092b11a1396613846f6b082e1e1ee16ea270c895ec6e4f553a13716304","d065623a7d943c6e5a20ca9667aa3c41e639e153600e26ca0af5d7c643384670","c08dd490860b54ae20fa9090274da9ffa1ba163f00d1e462e913cf8c68c11ac1"]); 
search in (AlertEvidence,BehaviorEntities,CommonSecurityLog,DeviceBaselineComplianceProfiles,DeviceEvents,DeviceFileEvents,DeviceImageLoadEvents, DeviceLogonEvents,DeviceNetworkEvents,DeviceProcessEvents,DeviceRegistryEvents,DeviceFileCertificateInfo,DynamicEventCollection,EmailAttachmentInfo,OfficeActivity,SecurityEvent,ThreatIntelligenceIndicator) TimeGenerated between ((selectedTimestamp - 1m) .. (selectedTimestamp + 90d)) // from September 17th runs the search for 90 days, change the selectedTimestamp accordingly. and  (FileName in (fileName) or OldFileName in (fileName)  or ProfileName in (fileName)  or InitiatingProcessFileName in (fileName)  or InitiatingProcessParentFileName in (fileName)  or InitiatingProcessVersionInfoInternalFileName in (fileName)  or InitiatingProcessVersionInfoOriginalFileName in (fileName)  or PreviousFileName in (fileName)  or ProcessVersionInfoInternalFileName in (fileName) or ProcessVersionInfoOriginalFileName in (fileName) or DestinationFileName in (fileName) or SourceFileName in (fileName)or ServiceFileName in (fileName) or SHA256 in (FileSHA256)  or InitiatingProcessSHA256 in (FileSHA256))

Microsoft Sentinel also has a range of detection and threat hunting content that customers can use to detect the post exploitation activity detailed in this blog, in addition to Microsoft Defender XDR detections list above.

• Remote Management Monitoring Network Connections
• Level.io RMM File Signature
• AnyDesk RMM File Signature
• NinjaOne RMM File Signature
• Potential Impacket Execution
• Potential ransomware activity related to Cobalt Strike
• Cobalt DNS Beacon
• C2-NamedPipe
• Renamed Rclone Exfiltration
• Disable Or Modify Windows Defender
• Clearing of forensic evidence from event logs using wevtutil
• Suspicious Signin By AAD Connect Account

Indicators of compromise (IOCs)

The following list provides indicators of compromise (IOCs) observed during our investigation. We encourage our customers to investigate these indicators within their environments and implement detections and protections to identify any past related activity and prevent future attacks against their systems.

References

• The Rust Revolution: New Embargo Ransomware Steps In – Cyble
• Embargo Ransomware Group: The Interview (suspectfile.com)
• https://aadinternals.com/post/aadbackdoor/
• https://aadinternals.com/post/aad-deepdive/

Omri Refaeli, Tafat Gaspar, Vaibhav Deshmukh, Naya Hashem, Charles-Edouard Bettan

Microsoft Threat Intelligence Community

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn at https://www.linkedin.com/showcase/microsoft-threat-intelligence, and on X (formerly Twitter) at https://twitter.com/MsftSecIntel.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast: https://thecyberwire.com/podcasts/microsoft-threat-intelligence.

The post Storm-0501: Ransomware attacks expanding to hybrid cloud environments appeared first on Microsoft Security Blog.

Peach Sandstorm also continued conducting password spray attacks against the educational sector for infrastructure procurement and against the satellite, government, and defense sectors as primary targets for intelligence collection. In addition, Microsoft observed intelligence gathering and possible social engineering targeting organizations within the higher education, satellite, and defense sectors via the professional networking platform LinkedIn.

Microsoft assesses that Peach Sandstorm operates on behalf of the Iranian Islamic Revolutionary Guard Corps (IRGC) based on the group’s victimology and operational focus. Microsoft further assesses that Peach Sandstorm’s operations are designed to facilitate intelligence collection in support of Iranian state interests.

Microsoft tracks Peach Sandstorm campaigns and directly notifies customers who we observe have been targeted or compromised, providing them with the necessary information to help secure their environment. As part of our continuous monitoring, analysis, and reporting on the threat landscape, we are sharing our research on Peach Sandstorm’s use of Tickler to raise awareness of this threat actor’s evolving tradecraft and to educate organizations on how to harden their attack surfaces against this and similar activity. Microsoft published information on unrelated election interference linked to Iran in the most recent Microsoft Threat Analysis Center (MTAC) report.

Evolution of Peach Sandstorm tradecraft

In past campaigns, Peach Sandstorm has been observed to use password spray attacks to gain access to targets of interest with a high level of success. The threat actor has also conducted intelligence gathering via LinkedIn, researching organizations and individuals employed in the higher education, satellite, and defense sectors.

During the group’s latest operations, Microsoft observed new tactics, techniques, and procedures (TTPs) following initial access via password spray attacks or social engineering. Between April and July 2024, Peach Sandstorm deployed a new custom multi-stage backdoor, Tickler, and leveraged Azure infrastructure hosted in fraudulent, attacker-controlled Azure subscriptions for command-and-control (C2). Microsoft continuously monitors Azure, along with all Microsoft products and services, to ensure compliance with our terms of service. Microsoft has notified affected organizations and disrupted the fraudulent Azure infrastructure and accounts associated with this activity.

Intelligence gathering on LinkedIn

Going back to at least November 2021 and continuing through mid-2024, Microsoft observed Peach Sandstorm using multiple LinkedIn profiles masquerading as students, developers, and talent acquisition managers based in the US and Western Europe. Peach Sandstorm primarily used them to conduct intelligence gathering and possible social engineering against the higher education, satellite sectors, and related industries. The identified LinkedIn accounts were subsequently taken down. Information on LinkedIn’s policies and actions against inauthentic behavior on its platform is available here.

Password spray attacks as a common attack vector

Since at least February 2023, Microsoft has observed Peach Sandstorm carrying out password spray activity against thousands of organizations. In password spray attacks, threat actors attempt to authenticate to many different accounts using a single password or a list of commonly used passwords. In contrast to brute force attacks, which target a single account using many passwords, password spray attacks help adversaries maximize their chances for success and minimize the likelihood of automatic account lockouts.

Microsoft has observed that once Peach Sandstorm has verified a target account’s credentials using the password spray technique, the threat actor performed subsequent sign-ins to the compromised accounts from commercial VPN infrastructure.

In April and May 2024, Microsoft observed Peach Sandstorm conducting password spray attacks targeting organizations in the defense, space, education, and government sectors in the US and Australia. In particular, Peach Sandstorm continued to use the “go-http-client” user agent that they are known to leverage in password spray campaigns. While the password spray activity appeared consistently across sectors, Microsoft observed Peach Sandstorm exclusively leveraging compromised user accounts in the education sector to procure operational infrastructure. In these cases, the threat actor accessed existing Azure subscriptions or created one using the compromised account to host their infrastructure. The attacker-controlled Azure infrastructure then served as C2 or operational hops for Peach Sandstorm operations targeting the government, defense, and space sectors. Recent updates to security defaults in Azure, such as multi-factor authentication help ensure that Azure accounts are more resistant to account compromise techniques such as those used by Peach Sandstorm.

Tickler malware

Microsoft Threat Intelligence identified two samples of the Tickler malware, a custom multi-stage backdoor, that Peach Sandstorm deployed in compromised environments as recently as July 2024. The first sample was contained in an archive file named Network Security.zip alongside benign PDF files used as decoy documents. The archive file contained:

• YAHSAT NETWORK_INFRASTRUCTURE_SECURITY_GUIDE_20240421.pdf.exe – theTickler malware
• Yahsat Policy Guide- April 2024.pdf – a benign PDF
• YAHSAT NETWORK_INFRASTRUCTURE_SECURITY_GUIDE_20240421.pdf – a second benign PDF

YAHSAT NETWORK_INFRASTRUCTURE_SECURITY_GUIDE_20240421.pdf.exe is a 64-bit C/C++ based native PE file. The sample begins with a Process Environment Block (PEB) traversal to locate the in-memory address of file kernell32.dll.

Upon successful PEB traversal yielding the address of kernell32.dll in memory, the sample decrypts a string to LoadLibraryA and resolves its address, decrypts the string “kernel32.dll”, and loads it again using LoadLibraryA. The sample then launches the benign PDF file YAHSAT NETWORK_INFRASTRUCTURE_SECURITY_GUIDE_20240421.pdf as a decoy document.

The sample collects the network information from the host and sends it to the C2 URI via HTTP POST request, likely as a means for the threat actor to orient themselves on the compromised network. The below network information is an example generated in a lab environment:

We subsequently observed Peach Sandstorm iterating and improving on this initial sample. The second Tickler sample, sold.dll, is a Trojan dropper functionally identical to the previously identified sample. The malware downloads additional payloads from the C2 server, including a backdoor, a batch script to set persistence for this backdoor, and the following legitimate files:

• msvcp140.dll (SHA-256: dad53a78662707d182cdb230e999ef6effc0b259def31c196c51cc3e8c42a9b8)
• LoggingPlatform.dll (SHA-256: 56ac00856b19b41bc388ecf749eb4651369e7ced0529e9bf422284070de457b6)
• vcruntime140.dll (SHA-256: 22017c9b022e6f2560fee7d544a83ea9e3d85abee367f2f20b3b0448691fe2d4)
• Microsoft.SharePoint.NativeMessaging.exe (SHA-256: e984d9085ae1b1b0849199d883d05efbccc92242b1546aeca8afd4b1868c54f5)

The files msvcp140.dll, LoggingPlatform.dll, vcruntime140.dll, and Microsoft.SharePoint.NativeMessaging.exe are legitimate Windows signed binaries likely used for DLL sideloading.

Additionally, we observed the sample downloading the following malicious files:

• A batch script (SHA-256: 5df4269998ed79fbc997766303759768ce89ff1412550b35ff32e85db3c1f57b)
• A DLL file (SHA-256: fb70ff49411ce04951895977acfc06fa468e4aa504676dedeb40ba5cea76f37f)
• A DLL file (SHA-256: 711d3deccc22f5acfd3a41b8c8defb111db0f2b474febdc7f20a468f67db0350)

The batch script adds a registry Run key for a file called SharePoint.exe, likely used to load the malicious DLL files above, thus setting up persistence:

The two DLL files are both 64-bit C/C++ compiled PE DLL files and appear to be functionally identical to the previously analyzed samples. As fully functional backdoors, they can run the following commands:

• systeminfo – Gather system information
• dir – List directory
• run – Execute command
• delete – Delete file
• interval – Sleep interval
• upload – Download file from the C2
• download – Upload file to the C2

Azure resources abuse

Microsoft observed Peach Sandstorm creating Azure tenants using Microsoft Outlook email accounts and creating Azure for Students subscriptions in these tenants. Additionally, the group leveraged compromised user accounts in the Azure tenants of organizations in the education sector to do the same. Within these subscriptions, Peach Sandstorm subsequently created Azure resources for use as C2 for the backdoor. Of note, we have observed multiple Iranian groups, including Smoke Sandstorm, use similar techniques in recent months. The following resources were created by Peach Sandstorm for use as Tickler C2 nodes:

• subreviews.azurewebsites[.]net 
• satellite2.azurewebsites[.]net 
• nodetestservers.azurewebsites[.]net 
• satellitegardens.azurewebsites[.]net 
• softwareservicesupport.azurewebsites[.]net
• getservicessuports.azurewebsites[.]net
• getservicessupports.azurewebsites[.]net 
• getsupportsservices.azurewebsites[.]net 
• satellitespecialists.azurewebsites[.]net
• satservicesdev.azurewebsites[.]net
• servicessupports.azurewebsites[.]net
• websupportprotection.azurewebsites[.]net 
• supportsoftwarecenter.azurewebsites[.]net
• centersoftwaresupports.azurewebsites[.]net
• softwareservicesupports.azurewebsites[.]net
• getsdervicessupoortss.azurewebsites[.]net

Post-compromise activity

In the past year, Peach Sandstorm has successfully compromised several organizations, primarily in the aforementioned sectors, using bespoke tooling. Once Peach Sandstorm gains access to an organization, the threat actor is known to perform lateral movement and actions on objectives using the following techniques:

Moving laterally via Server Message Block (SMB)

After compromising a European defense organization, Peach Sandstorm threat actors moved laterally via SMB. SMB lateral movement is a technique used by threat actors to move from one compromised machine to another within a network by exploiting the SMB protocol. This protocol, which is used for sharing files, printers, and other resources on a network, could be misused by attackers to propagate their access and gain control over multiple systems.

Downloading and installing a remote monitoring and management (RMM) tool

In an older intrusion against a multinational pharmaceutical company not associated with the campaign discussed in this blog, after a likely successful password spray attack, Peach Sandstorm attempted to download and install AnyDesk, a commercial RMM tool. AnyDesk has a range of capabilities that allow users to remotely access a network, persist in a compromised environment, and enable command and control. The convenience and utility of a tool like AnyDesk is amplified by the fact that it might be permitted by application controls in environments where it is used legitimately by IT support personnel or system administrators.

Taking an Active Directory (AD) snapshot

In at least one intrusion against a Middle East-based satellite operator, Peach Sandstorm actors compromised a user using a malicious ZIP file delivered via Microsoft Teams message followed by dropping AD Explorer and taking an AD snapshot. An AD snapshot is a read-only, point-in-time copy of the AD database and related files, which can be used for various legitimate administrative tasks. These snapshots can also be exploited by threat actors for malicious purposes.

Mitigations

To harden networks against Peach Sandstorm activity, defenders can implement the following:

• Reset account passwords for any accounts targeted during a password spray attack. If a targeted account had system-level permissions, further investigation may be warranted. 
• Revoke session cookies in addition to resetting passwords. 
  • Revoke any MFA setting changes made by the attacker on any compromised users’ accounts. 
  • Require re-challenging MFA for MFA updates as the default. 
• Implement the Azure Security Benchmark and general best practices for securing identity infrastructure, including:  
  • Create conditional access policies to allow or disallow access to the environment based on defined criteria. 
  • Block legacy authentication with Microsoft Entra by using Conditional Access. Legacy authentication protocols don’t have the ability to enforce multifactor authentication (MFA), so blocking such authentication methods will help prevent password spray attackers from taking advantage of the lack of MFA on those protocols. 
  • Enable AD FS web application proxy extranet lockout to protect users from potential password brute force compromise. 
• Secure accounts with credential hygiene: 
  • Practice the principle of least privilege and audit privileged account activity in your Microsoft Entra environments to help slow and stop attackers.  
  • Deploy Microsoft Entra Connect Health for Active Directory Federation Services (AD FS). This captures failed attempts as well as IP addresses recorded in AD FS logs for bad requests in the Risky IP report. 
  • Use Microsoft Entra password protection to help detect and block known weak passwords and their variants. 
  • Turn on identity protection in Microsoft Entra to monitor for identity-based risks and create policies for risky sign ins. 
• Comply with the recent MFA enforcement policy requiring all Azure accounts to utilize MFA. Keep MFA always-on for privileged accounts and apply risk-based MFA for normal accounts.
  • Consider transitioning to a passwordless primary authentication method, such as Azure MFA, certificates, or Windows Hello for Business. 
• Secure remote desktop protocol (RDP) or Windows Virtual Desktop endpoints with MFA to harden against password spray or brute force attacks.

To protect against password spray attacks, implement the following mitigations:

• Eliminate insecure passwords.
• Educate users to review sign-in activity and mark suspicious sign-in attempts as “This wasn’t me”.
• Reset account passwords for any accounts targeted during a password spray attack. If a targeted account had system-level permissions, further investigation may be warranted.
• Detect, investigate, and remediate identity-based attacks using solutions like Microsoft Entra ID Protection.
• Investigate compromised accounts using Microsoft Purview Audit (Premium).
• Enforce on-premises Microsoft Entra Password Protection for Microsoft Active Directory Domain Services.
• Use risk detections for user sign-ins to trigger multifactor authentication or password changes.
• Investigate any possible password spray activity using the password spray investigation playbook.

Strengthen endpoints against attacks by following these steps:

• Turn on cloud-delivered protection in Microsoft Defender Antivirus or the equivalent for your antivirus product to help cover rapidly evolving attacker tools and techniques. 
• Enable real-time protection in Microsoft Defender Antivirus or the equivalent for your antivirus product. 
• Detect and block potentially unwanted applications through Microsoft Defender for Endpoint. 
• Run endpoint detection and response (EDR) in block mode so that Microsoft Defender for Endpoint can help block malicious artifacts, even when your non-Microsoft antivirus does not detect the threat, or when Microsoft Defender Antivirus is running in passive mode. EDR in block mode works behind the scenes to help remediate malicious artifacts that are detected post-compromise. 
• Turn on attack surface reduction rules to help prevent common attack techniques:  
  • Block executable files from running unless they meet a prevalence, age, or trusted list criterion  
  • Block execution of potentially obfuscated scripts 
• Implement anomaly detection policies in Microsoft Defender for Cloud Apps. 
• Enable protections in Microsoft Defender for Endpoint to help safeguard against malicious sites and internet-based threats. 
  • Network protection 
  • Web protection 
• Enable tamper protection within Microsoft Defender for Endpoint to help prevent threat actors from disabling or changing security features, such as virus and threat protection.

Microsoft Defender XDR detections

Microsoft Defender Antivirus

Microsoft Defender Antivirus detects components of this threat as the following malware:

• TrojanDownloader:Win64/Tickler
• Backdoor:Win64/Tickler

Microsoft Defender for Endpoint

The following Microsoft Defender for Endpoint alerts can indicate associated threat activity:

• Peach Sandstorm actor activity detected

The following alerts might also indicate threat activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Password spraying
• Unfamiliar Sign-in properties
• An executable file loaded an unexpected DLL file

Microsoft Defender for Identity

The following Microsoft Defender for Identity alerts can indicate activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Atypical travel
• Suspicious behavior: Impossible travel activity

Microsoft Defender for Cloud Apps

The following Microsoft Defender for Cloud Apps alerts can indicate activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Activity from a Tor IP address
• Suspicious Administrative Activity
• Impossible travel activity
• Multiple failed login attempts
• Activity from an anonymous proxy

Threat intelligence reports

Microsoft Defender Threat Intelligence customers can use the following reports in Microsoft products to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection information, and recommended actions to help prevent, mitigate, or respond to associated threats found in customer environments.

Microsoft Defender Threat Intelligence

• Abuse of remote monitoring and management tools
• DLL sideloading and DLL search order hijacking

Hunting queries

Microsoft Defender XDR

Microsoft Defender XDR customers can run the following query to find related activity in their networks:

Failed logon activity

The following query identifies failed attempts to sign-in from multiple sources that originate from a single ISP. Attackers distribute attacks from multiple IP addresses across a single service provider to evade detection. Run query 

IdentityLogonEvents
| where Timestamp > ago(4h)
| where ActionType == "LogonFailed"
| where isnotempty(AccountObjectId)
| summarize TargetCount = dcount(AccountObjectId), TargetCountry = dcount(Location), TargetIPAddress = dcount(IPAddress) by ISP
| where TargetCount >= 100
| where TargetCountry >= 5
| where TargetIPAddress >= 25

Connectivity to C2s

The following queries identifies connectivity to Peach Sandstorm created Azure App Service apps for command and control. Run query

let domainList = dynamic(["subreviews.azurewebsites.net", 
    "satellite2.azurewebsites.net",
    "nodetestservers.azurewebsites.net", 
    "satellitegardens.azurewebsites.net",
    "softwareservicesupport.azurewebsites.net",
    "getservicessuports.azurewebsites.net",
    "getservicessupports.azurewebsites.net",
    "getsupportsservices.azurewebsites.net",
    "satellitespecialists.azurewebsites.net",
    "satservicesdev.azurewebsites.net",
    "servicessupports.azurewebsites.net",
    "websupportprotection.azurewebsites.net ",
    "supportsoftwarecenter.azurewebsites.net",
    "centersoftwaresupports.azurewebsites.net"
    "softwareservicesupports.azurewebsites.net",
    "getsdervicessupoortss.azurewebsites.net"]);union
(
    DnsEvents
    | where QueryType has_any(domainList) or Name has_any(domainList)
    | project TimeGenerated, Domain = QueryType, SourceTable = "DnsEvents"
),
(
    IdentityQueryEvents
    | where QueryTarget has_any(domainList)
    | project Timestamp, Domain = QueryTarget, SourceTable = "IdentityQueryEvents"
),
(
    DeviceNetworkEvents
    | where RemoteUrl has_any(domainList)
    | project Timestamp, Domain = RemoteUrl, SourceTable = "DeviceNetworkEvents"
),
(
    DeviceNetworkInfo
    | extend DnsAddresses = parse_json(DnsAddresses), ConnectedNetworks = parse_json(ConnectedNetworks)
    | mv-expand DnsAddresses, ConnectedNetworks
    | where DnsAddresses has_any(domainList) or ConnectedNetworks.Name has_any(domainList)
    | project Timestamp, Domain = coalesce(DnsAddresses, ConnectedNetworks.Name), SourceTable = "DeviceNetworkInfo"
),
(
    VMConnection
    | extend RemoteDnsQuestions = parse_json(RemoteDnsQuestions), RemoteDnsCanonicalNames = parse_json(RemoteDnsCanonicalNames)
    | mv-expand RemoteDnsQuestions, RemoteDnsCanonicalNames
    | where RemoteDnsQuestions has_any(domainList) or RemoteDnsCanonicalNames has_any(domainList)
    | project TimeGenerated, Domain = coalesce(RemoteDnsQuestions, RemoteDnsCanonicalNames), SourceTable = "VMConnection"
),
(
    W3CIISLog
    | where csHost has_any(domainList) or csReferer has_any(domainList)
    | project TimeGenerated, Domain = coalesce(csHost, csReferer), SourceTable = "W3CIISLog"
),
(
    EmailUrlInfo
    | where UrlDomain has_any(domainList)
    | project Timestamp, Domain = UrlDomain, SourceTable = "EmailUrlInfo"
),
(
    UrlClickEvents
    | where Url has_any(domainList)
    | project Timestamp, Domain = Url, SourceTable = "UrlClickEvents"
)
| order by TimeGenerated desc

Malicious file activity

The following query will surface events involving malicious files related to this activity. Run query

let fileHashes = dynamic(["711d3deccc22f5acfd3a41b8c8defb111db0f2b474febdc7f20a468f67db0350", "fb70ff49411ce04951895977acfc06fa468e4aa504676dedeb40ba5cea76f37f", "5df4269998ed79fbc997766303759768ce89ff1412550b35ff32e85db3c1f57b", "ccb617cc7418a3b22179e00d21db26754666979b4c4f34c7fda8c0082d08cec4", "7eb2e9e8cd450fc353323fd2e8b84fbbdfe061a8441fd71750250752c577d198"]);
union
(
    DeviceFileEvents
    | where SHA256 in (fileHashes)
    | project Timestamp, FileHash = SHA256, SourceTable = "DeviceFileEvents"
),
(
    DeviceEvents
    | where SHA256 in (fileHashes)
    | project Timestamp, FileHash = SHA256, SourceTable = "DeviceEvents"
),
(
    DeviceImageLoadEvents
    | where SHA256 in (fileHashes)
    | project Timestamp, FileHash = SHA256, SourceTable = "DeviceImageLoadEvents"
),
(
    DeviceProcessEvents
    | where SHA256 in (fileHashes)
    | project Timestamp, FileHash = SHA256, SourceTable = "DeviceProcessEvents"
)
| order by Timestamp desc

Microsoft Sentinel

Microsoft Sentinel customers can use the TI Mapping analytics (a series of analytics all prefixed with ‘TI map’) to automatically match the malicious domain indicators mentioned in this blog post with data in their workspace. If the TI Map analytics are not currently deployed, customers can install the Threat Intelligence solution from the Microsoft Sentinel Content Hub to have the analytics rule deployed in their Sentinel workspace.

• Signin Password Spray
• New Location Azure AD Sign Ins
• Enumeration of users & groups for lateral movement
• SMB shares Discovery
• Anomaly in SMB Traffic
• AnyDesk Net Connection
• AnyDesk – File Signature
• AnyDesk – Create Process
• DCSync Attack Detection

Indicators of compromise

Domains

• subreviews.azurewebsites[.]net 
• satellite2.azurewebsites[.]net 
• nodetestservers.azurewebsites[.]net 
• satellitegardens.azurewebsites[.]net 
• softwareservicesupport.azurewebsites[.]net
• getservicessuports.azurewebsites[.]net
• getservicessupports.azurewebsites[.]net 
• getsupportsservices.azurewebsites[.]net 
• satellitespecialists.azurewebsites[.]net
• satservicesdev.azurewebsites[.]net
• servicessupports.azurewebsites[.]net
• websupportprotection.azurewebsites[.]net 
• supportsoftwarecenter.azurewebsites[.]net
• centersoftwaresupports.azurewebsites[.]net
• softwareservicesupports.azurewebsites[.]net
• getsdervicessupoortss.azurewebsites[.]net

Tickler samples and related indicators

• YAHSAT NETWORK_INFRASTRUCTURE_SECURITY_GUIDE_20240421.pdf.exe (SHA-256:  7eb2e9e8cd450fc353323fd2e8b84fbbdfe061a8441fd71750250752c577d198)
• Sold.dll (SHA-256: ccb617cc7418a3b22179e00d21db26754666979b4c4f34c7fda8c0082d08cec4)
• Batch script (SHA-256: 5df4269998ed79fbc997766303759768ce89ff1412550b35ff32e85db3c1f57b)
• Malicious DLL (SHA-256: fb70ff49411ce04951895977acfc06fa468e4aa504676dedeb40ba5cea76f37f)
• Malicious DLL (SHA-256: 711d3deccc22f5acfd3a41b8c8defb111db0f2b474febdc7f20a468f67db0350)

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn at https://www.linkedin.com/showcase/microsoft-threat-intelligence and on X (formerly Twitter) at https://twitter.com/MsftSecIntel.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast: https://thecyberwire.com/podcasts/microsoft-threat-intelligence.

The post Peach Sandstorm deploys new custom Tickler malware in long-running intelligence gathering operations appeared first on Microsoft Security Blog.

The vulnerability, identified as CVE-2024-37085, involves a domain group whose members are granted full administrative access to the ESXi hypervisor by default without proper validation. Microsoft disclosed the findings to VMware through Coordinated Vulnerability Disclosure (CVD) via Microsoft Security Vulnerability Research (MSVR), and VMWare released a security update. Microsoft recommends ESXi server administrators to apply the updates released by VMware to protect their servers from related attacks, and to follow the mitigation and protection guidance we provide in this blog post. We thank VMWare for their collaboration in addressing this issue.

This blog post presents analysis of the CVE-2024-37085, as well as details of an attack that was observed by Microsoft to exploit the vulnerability. We’re sharing this research to emphasize the importance of collaboration among researchers, vendors, and the security community to continuously advance defenses for the larger ecosystem. As part of Microsoft’s commitment to improve security for all, we will continue to share intelligence and work with the security community to help protect users and organizations across platforms.

CVE-2024-37085 vulnerability analysis

Microsoft security researchers identified a new post-compromise technique utilized by ransomware operators like Storm-0506, Storm-1175, Octo Tempest, and Manatee Tempest in numerous attacks. In several cases, the use of this technique has led to Akira and Black Basta ransomware deployments. The technique includes running the following commands, which results in the creation of a group named “ESX Admins” in the domain and adding a user to it:

net group “ESX Admins” /domain /add

net group “ESX Admins” username /domain /add

While investigating the attacks and the described behavior, Microsoft researchers discovered that the threat actors’ purpose for using this command was to utilize a vulnerability in domain-joined ESXi hypervisors that allows the threat actor to elevate their privileges to full administrative access on the ESXi hypervisor. This finding was reported as part of a vulnerability disclosure to VMware earlier this year.

Further analysis of the vulnerability revealed that VMware ESXi hypervisors joined to an Active Directory domain consider any member of a domain group named “ESX Admins” to have full administrative access by default. This group is not a built-in group in Active Directory and does not exist by default. ESXi hypervisors do not validate that such a group exists when the server is joined to a domain and still treats any members of a group with this name with full administrative access, even if the group did not originally exist. Additionally, the membership in the group is determined by name and not by security identifier (SID).

Microsoft researchers identified three methods for exploiting this vulnerability:

1. Adding the “ESX Admins” group to the domain and adding a user to it – This method is actively exploited in the wild by the abovementioned threat actors. In this method, if the “ESX Admins” group doesn’t exist, any domain user with the ability to create a group can escalate privileges to full administrative access to domain-joined ESXi hypervisors by creating such a group, and then adding themselves, or other users in their control, to the group.
2. Renaming any group in the domain to “ESX Admins” and adding a user to the group or use an existing group member – This method is similar to the first, but in this case the threat actor needs a user that has the capability to rename some arbitrary groups and rename one of them to “ESX Admins”. The threat actor can then add a user or use a user that already exists in the group, to escalate privileges to full administrative access. This method was not observed in the wild by Microsoft.
3. ESXi hypervisor privileges refresh – Even if the network administrator assigns any other group in the domain to be the management group for the ESXi hypervisor, the full administrative privileges to members of the “ESX Admins” group are not immediately removed and threat actors still could abuse it. This method was not observed in the wild by Microsoft.

Successful exploitation leads to full administrative access to the ESXi hypervisors, allowing threat actors to encrypt the file system of the hypervisor, which could affect the ability of the hosted servers to run and function. It also allows the threat actor to access hosted VMs and possibly to exfiltrate data or move laterally within the network.

Ransomware operators targeting ESXi hypervisors

Over the last year, we have seen ransomware actors targeting ESXi hypervisors to facilitate mass encryption impact in few clicks, demonstrating that ransomware operators are constantly innovating their attack techniques to increase impact on the organizations they target.

ESXi is a popular product in many corporate networks, and in recent years, we have observed ESXi hypervisors become a favored target for threat actors. These hypervisors could be convenient targets if ransomware operators want to stay under the SOC’s radar because of the following factors:

1. Many security products have limited visibility and protection for an ESXi hypervisor.
2. Encrypting an ESXi hypervisor file system allows one-click mass encryption, as hosted VMs are impacted. This could provide ransomware operators with more time and complexity in lateral movement and credential theft on each device they access.

Therefore, many ransomware threat actors like Storm-0506, Storm-1175, Octo Tempest, Manatee Tempest, and others support or sell ESXi encryptors like Akira, Black Basta, Babuk, Lockbit, and Kuiper (Figure 1). The number of Microsoft Incident Response (Microsoft IR) engagements that involved the targeting and impacting ESXi hypervisors have more than doubled in the last three years.

Storm-0506 Black Basta ransomware deployment

Earlier this year, an engineering firm in North America was affected by a Black Basta ransomware deployment by Storm-0506. During this attack, the threat actor used the CVE-2024-37085 vulnerability to gain elevated privileges to the ESXi hypervisors within the organization.

The threat actor gained initial access to the organization via Qakbot infection, followed by the exploitation of a Windows CLFS vulnerability (CVE-2023-28252) to elevate their privileges on affected devices. The threat actor then used Cobalt Strike and Pypykatz (a Python version of Mimikatz) to steal the credentials of two domain administrators and to move laterally to four domain controllers.

On the compromised domain controllers, the threat actor installed persistence mechanisms using custom tools and a SystemBC implant. The actor was also observed attempting to brute force Remote Desktop Protocol (RDP) connections to multiple devices as another method for lateral movement, and then again installing Cobalt Strike and SystemBC. The threat actor then tried to tamper with Microsoft Defender Antivirus using various tools to avoid detection.

Microsoft observed that the threat actor created the “ESX Admins” group in the domain and added a new user account to it, following these actions, Microsoft observed that this attack resulted in encrypting of the ESXi file system and losing functionality of the hosted virtual machines on the ESXi hypervisor.   The actor was also observed to use PsExec to encrypt devices that are not hosted on the ESXi hypervisor. Microsoft Defender Antivirus and automatic attack disruption in Microsoft Defender for Endpoint were able to stop these encryption attempts in devices that had the unified agent for Defender for Endpoint installed.

Mitigation and protection guidance

Microsoft recommends organizations that use domain-joined ESXi hypervisors to apply the security update released by VMware to address CVE-2024-37085. The following guidelines will also help organizations protect their network from attacks:

• Install software updates – Make sure to install the latest security updates released by VMware on all domain-joined ESXi hypervisors. If installing software updates is not possible, you can use the following recommendations to reduce the risk:
  • Validate the group “ESX Admins” exists in the domain and is hardened.
  • Manually deny access by this group by changing settings in the ESXi hypervisor itself. If full admin access for the Active Directory ESX admins group is not desired, you can disable this behavior using the advanced host setting: ‘Config.HostAgent.plugins.hostsvc.esxAdminsGroupAutoAdd’.
  • Change the admin group to a different group in the ESXi hypervisor.
  • Add custom detections in XDR/SIEM for the new group name.  
  • Configure sending ESXi logs to a SIEM system and monitor suspicious full administrative access.
• Credential hygiene – To utilize the different vulnerability methods, threat actors require control of a highly privileged user in the organization. Therefore, our recommendation is making sure to protect your highly privileged accounts in the organization, especially those that can manage other domain groups:
  • Enforce multifactor authentication (MFA) on all accounts, remove users excluded from MFA, and strictly require MFA from all devices, in all locations, always.
  • Enable passwordless authentication methods (for example, Windows Hello, FIDO keys, or Microsoft Authenticator) for accounts that support passwordless. For accounts that still require passwords, use authenticator apps like Microsoft Authenticator for MFA. Refer to this article for the different authentication methods and features.
  • Isolate privileged accounts from productivity accounts to protect administrative access to the environment. Refer to this article to understand best practices.
• Improve critical assets posture – Identify your critical assets in the network, such as  ESXi hypervisors and vCenters (a centralized platform for controlling VMware vSphere environments), and make sure to get them protected with latest security updates, proper monitoring procedures and backup and recovery plans. More information can be found in this article.
• Identify vulnerable assets – Use Microsoft Defender Vulnerability Management to reduce risk with continuous vulnerability assessment of ESXi hypervisor out of the box.

Microsoft Defender XDR detections

Microsoft Defender for Endpoint             

The following Microsoft Defender for Endpoint alerts can indicate associated threat activity:

• Suspicious modifications to ESX Admins group

The following alerts might also indicate threat activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• New group added suspiciously
• Suspicious Windows account manipulation
• Compromised account conducting hands-on-keyboard attack

Microsoft Defender for Identity

The following Microsoft Defender for Identity alerts can indicate associated threat activity:

• Suspicious creation of ESX group

Threat intelligence reports

Microsoft customers can use the following reports in Microsoft Defender Threat Intelligence to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection information, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments:

• Storm-0506
• Storm-1175
• Octo Tempest 
• Manatee Tempest
• Akira
• Black Basta

Hunting queries

Microsoft Defender XDR

Microsoft Defender XDR customers can run the following queries to find related activity in their networks

This query identifies ESXi hypervisors in the organization:

DeviceInfo
| where OSDistribution =~ "ESXi"
| summarize arg_max(Timestamp, *) by DeviceId

This query identifies ESX Admins group changes in the Active directory:

IdentityDirectoryEvents
| where Timestamp >= ago(30d)
| where AdditionalFields has ('esx admins')

The following queries are for assessing the already discovered ESXi with the Microsoft Defender Vulnerability Management information:

DeviceInfo
| where OSDistribution =~ "ESXi"
| summarize arg_max(Timestamp, *) by DeviceId
| join kind=inner (DeviceTvmSoftwareVulnerabilities) on DeviceId
DeviceInfo
| where OSDistribution =~ "ESXi"
| summarize arg_max(Timestamp, *) by DeviceId
| join kind=inner (DeviceTvmSecureConfigurationAssessment) on DeviceId

Microsoft Sentinel

Microsoft Sentinel customers can use the TI Mapping analytics (a series of analytics all prefixed with ‘TI map’) to automatically match the malicious domain indicators mentioned in this blog post with data in their workspace. If the TI Map analytics are not currently deployed, customers can install the Threat Intelligence solution from the Microsoft Sentinel Content Hub to have the analytics rule deployed in their Sentinel workspace.

Microsoft Sentinel also has a range of hunting queries available in Sentinel GitHub repo or as part of Sentinel solutions that customers can use to detect the activity detailed in this blog in addition to Microsoft Defender detections. These hunting queries include the following:

Qakbot:

• Qakbot hunting queries

Cobalt Strike:

• Cobalt Strike DNS Beaconing
• Potential ransomware activity related to Cobalt Strike
• Suspicious named pipes
• Cobalt Strike Invocation using WMI

References

• https://knowledge.broadcom.com/external/article?legacyId=1025569
• https://core.vmware.com/vmware-vsphere-8-security-configuration-guide
• https://blogs.vmware.com/vsphere/2012/09/joining-vsphere-hosts-to-active-directory.html
• https://blogs.vmware.com/security/2022/09/esxi-targeting-ransomware-the-threats-that-are-after-your-virtual-machines-part-1.html
• https://www.sygnia.co/blog/esxi-ransomware-attacks/?blaid=6088911https://news.sophos.com/en-us/2023/12/21/akira-again-the-ransomware-that-keeps-on-taking/
• https://www.darkreading.com/cloud-security/agenda-ransomware-vmware-esxi-servers
• https://blog.checkpoint.com/2023/02/06/massive-ransomware-attack-targets-vmware-esxi-servers/amp/
• https://www.bleepingcomputer.com/news/security/massive-esxiargs-ransomware-attack-targets-vmware-esxi-servers-worldwide/amp/

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn at https://www.linkedin.com/showcase/microsoft-threat-intelligence, and on X (formerly Twitter) at https://twitter.com/MsftSecIntel.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast: https://thecyberwire.com/podcasts/microsoft-threat-intelligence.

The post Ransomware operators exploit ESXi hypervisor vulnerability for mass encryption appeared first on Microsoft Security Blog.

Chances are you’ve heard the phrase “attackers don’t break in, they log in.” Identities have evolved to be the most targeted asset, because they enable cyber criminals to move and operate across environments to achieve their goals. In 2023, identity-based attacks reached a record-high with 30 billion attempted password attacks each month, as cyber-criminals capitalize on the smallest misconfigurations and gaps in your identity protection.  

As customers have applied MFA, device compliance, and other Zero Trust core principles to their identity environments, attackers have shifted to attacking the identity infrastructure itself. While it is critical to protect all identities – identifying, preventing, detecting and responding to attacks on the Identity admins, apps, and services that provide the foundation of your Zero Trust platform is more critical than ever. That’s why it’s critical for organizations to build a holistic approach to defend their identity estate across both – on-prem infrastructure and cloud identities – by making Identity Threat Detection and Response (ITDR) a cornerstone of their defense strategy. KuppingerCole defines ITDR as a class of security solutions designed to proactively detect, investigate, and respond to identity-related threats and vulnerabilities in an organization’s IT environment. 

Today we are thrilled to announce that Microsoft has been recognized as an overall leader in the KuppingerCole Leadership Compass Identity Threat Detection and Response: IAM Meets the SOC. The report calls out our strengths across key capabilities ranging from identity posture to remediation, while further highlighting Microsoft’s commitment to protecting all organizations. VP KuppingerCole US and Global Head of Research Strategy Mike Neuenschwander states that “Microsoft’s approach to ITDR is refreshingly open, including integration with other cloud identity platforms such as AWS, Google Cloud, and Okta.”.  

Figure 1: ITDR Leadership compass with Microsoft as a leader

Streamline your identity protection with ITDR and generative AI  

At Microsoft, we look at ITDR as a set of capabilities at the intersection of Identity and Access Management (IAM) and Extended Detection and Response (XDR). Designed to break down organizational silos and optimize collaboration and effectiveness of identity and SOC teams, we built a seamless integration between Microsoft Entra ID and Microsoft Defender XDR that empowers organizations to reinforce their security boundary with complete protection across their hybrid identity landscape.  Further, generative AI in the form of Microsoft Copilot for Security is embedded across all touchpoints, helping security and IT professionals respond to cyber threats, process signals, and assess risk exposure at the speed and scale of AI. 

As organizations begin to implement their ITDR strategies, they should consider 4 key areas: 

• Enforce secure, adaptive access: Adopting a comprehensive, defense-in-depth strategy that spans identities, endpoints, and networks is the starting point of any ITDR initiative. Implementing consistent identity and network access policies from a single unified engine across public and private networks is critical to protecting identities and securing access to resources. The Zero Trust Network Access model of Microsoft Entra Private Access enables secure connectivity to private resources from Windows, iOS, Mac, and Android operating systems and across any port and protocol, including SMB, RDP, FTP, SSH, SAP, printing, and all other TCP/UDP based protocols to significantly reduce the risk of potential breaches. Using advanced user and entity behavioral analytics (UEBA) in Microsoft Entra ID Protection, Conditional Access policies make real-time access decisions based on contextual factors such as user, device, location, network, and real-time risk information to control what a specific user can access and how and when they have access seamlessly across on-premises and cloud environments. Analyze risk signals in real time and automatically block access or prompt re-authentication, like MFA, to stop suspicious activity in real time and before a breach occurs.  
• Proactively protect your on-premises resources and harden your identity posture: Misconfigurations in identity infrastructure, permissions, or access controls are the Achillies’ heel of identity security. All it takes is one compromised user account, infected device, or an open port for an attacker to access and laterally move anywhere inside your network. These breaches-waiting-to-happen can have far-reaching consequences as Identities have become an integral part of almost every element of modern security practices. Microsoft provides detailed, identity-specific posture recommendations spanning on-premises Active Directory environments, Microsoft Entra ID deployments and even other common identity solutions all within the context of a broader security posture score. 
• Disrupt and remediate identity threats at machine speed: Automatic attack disruption is an out-of-the-box capability in Defender XDR that stops the progression and limits the impact of some of the most sophisticated attacks that involve identity compromise. Using the significant breadth of our signals, it not only disrupts ongoing attacks but accurately predicts the attacker’s next move and proactively blocks it with 99% confidence. Ransomware campaigns are now disrupted within an average of 3 minutes. Our powerful capabilities support identity-involved attacks like business email compromise, adversary-in-the-middle, and can even disrupt Ransomware campaigns within an average of 3 minutes. 
• Augment your security teams with generative AI: Microsoft Copilot for Security is the first generative AI security product to help protect organizations at machine speed and scale. Copilot for Security is an AI assistant for security teams that builds on the latest in large language models. Copilot is native within the existing Entra and Defender experiences, helping identity and SOC teams prioritize, understand and act upon identity risks and security incidents with step-by-step recommendations in seconds.  

As the sophistication and prevalence of identity-based attacks continue to grow, ITDR is becoming increasingly critical to modern cybersecurity and we are excited to see KuppingerCole highlight this in their latest report. Looking forward, we will continue to integrate our industry-leading solution and AI capabilities to help our customers future-proof their defenses and stay resilient against evolving cyberthreats in the workforce identity space. 

​​To learn more about Microsoft’s ITDR solution visit our website. Bookmark the Security blog to keep up with our expert coverage on security matters. Also, follow us on LinkedIn (Microsoft Security) and X (@MSFTSecurity) for the latest news and updates on cybersecurity. 

The post Microsoft named an overall leader in KuppingerCole Leadership Compass for ITDR appeared first on Microsoft Security Blog.

Forest Blizzard often uses publicly available exploits in addition to CVE-2022-38028, such as CVE-2023-23397. Linked to the Russian General Staff Main Intelligence Directorate (GRU) by the United States and United Kingdom governments, Forest Blizzard primarily focuses on strategic intelligence targets and differs from other GRU-affiliated and sponsored groups, which Microsoft has tied to destructive attacks, such as Seashell Blizzard (IRIDIUM) and Cadet Blizzard (DEV-0586). Although Russian threat actors are known to have exploited a set of similar vulnerabilities known as PrintNightmare (CVE-2021-34527 and CVE-2021-1675), the use of GooseEgg in Forest Blizzard operations is a unique discovery that had not been previously reported by security providers. Microsoft is committed to providing visibility into observed malicious activity and sharing insights on threat actors to help organizations protect themselves. Organizations and users are to apply the CVE-2022-38028 security update to mitigate this threat, while Microsoft Defender Antivirus detects the specific Forest Blizzard capability as HackTool:Win64/GooseEgg.

This blog provides technical information on GooseEgg, a unique Forest Blizzard capability. In addition to patching, this blog details several steps users can take to defend themselves against attempts to exploit Print Spooler vulnerabilities. We also provide additional recommendations, detections, and indicators of compromise. As with any observed nation-state actor activity, Microsoft directly notifies customers that have been targeted or compromised, providing them with the necessary information to secure their accounts.

Who is Forest Blizzard?

Forest Blizzard primarily targets government, energy, transportation, and non-governmental organizations in the United States, Europe, and the Middle East. Microsoft has also observed Forest Blizzard targeting media, information technology, sports organizations, and educational institutions worldwide. Since at least 2010, the threat actor’s primary mission has been to collect intelligence in support of Russian government foreign policy initiatives. The United States and United Kingdom governments have linked Forest Blizzard to Unit 26165 of the Russian Federation’s military intelligence agency, the Main Intelligence Directorate of the General Staff of the Armed Forces of the Russian Federation (GRU). Other security researchers have used GRU Unit 26165, APT28, Sednit, Sofacy, and Fancy Bear to refer to groups with similar or related activities.

GooseEgg

Microsoft Threat Intelligence assesses Forest Blizzard’s objective in deploying GooseEgg is to gain elevated access to target systems and steal credentials and information. While this actor’s TTPs and infrastructure specific to the use of this tool can change at any time, the following sections provide additional details on Forest Blizzard tactics, techniques, and procedures (TTPs) in past compromises.

Launch, persistence, and privilege escalation

Microsoft has observed that, after obtaining access to a target device, Forest Blizzard uses GooseEgg to elevate privileges within the environment. GooseEgg is typically deployed with a batch script, which we have observed using the name execute.bat and doit.bat. This batch script writes the file servtask.bat, which contains commands for saving off/compressing registry hives. The batch script invokes the paired GooseEgg executable and sets up persistence as a scheduled task designed to run servtask.bat.

The GooseEgg binary—which has included but is not limited to the file names justice.exe and DefragmentSrv.exe—takes one of four commands, each with different run paths. While the binary appears to launch a trivial given command, in fact the binary does this in a unique and sophisticated manner, likely to help conceal the activity.

The first command issues a custom return code 0x6009F49F and exits; which could be indicative of a version number. The next two commands trigger the exploit and launch either a provided dynamic-link library (DLL) or executable with elevated permissions. The fourth and final command tests the exploit and checks that it has succeeded using the whoami command.

Microsoft has observed that the name of an embedded malicious DLL file typically includes the phrase “wayzgoose”; for example, wayzgoose23.dll. This DLL, as well as other components of the malware, are deployed to one of the following installation subdirectories, which is created under C:\ProgramData. A subdirectory name is selected from the list below:

• Microsoft
• Adobe
• Comms
• Intel
• Kaspersky Lab
• Bitdefender
• ESET
• NVIDIA
• UbiSoft
• Steam

A specially crafted subdirectory with randomly generated numbers and the format string \v%u.%02u.%04u is also created and serves as the install directory. For example, a directory that looks like C:\ProgramData\Adobe\v2.116.4405 may be created. The binary then copies the following driver stores to this directory:

• C:\Windows\System32\DriverStore\FileRepository\pnms003.inf_*
• C:\Windows\System32\DriverStore\FileRepository\pnms009.inf_*

Next, registry keys are created, effectively generating a custom protocol handler and registering a new CLSID to serve as the COM server for this “rogue” protocol. The exploit replaces the C: drive symbolic link in the object manager to point to the newly created directory. When the PrintSpooler attempts to load C:\Windows\System32\DriverStore\FileRepository\pnms009.inf_amd64_a7412a554c9bc1fd\MPDW-Constraints.js, it instead is redirected to the actor-controlled directory containing the copied driver packages.

The “MPDW-constraints.js” stored within the actor-controlled directory has the following patch applied to the convertDevModeToPrintTicket function:

function convertDevModeToPrintTicket(devModeProperties, scriptContext, printTicket)
{try{ printTicket.XmlNode.load('rogue9471://go'); } catch (e) {}

The above patch to the convertDevModeToPrintTicket function invokes the “rogue” search protocol handler’s CLSID during the call to RpcEndDocPrinter. This results in the auxiliary DLL wayzgoose.dll launching in the context of the PrintSpooler service with SYSTEM permissions. wayzgoose.dll is a basic launcher application capable of spawning other applications specified at the command line with SYSTEM-level permissions, enabling threat actors to perform other malicious activities such as installing a backdoor, moving laterally through compromised networks, and remotely executing code.

Recommendations

Microsoft recommends the following mitigations defend against attacks that use GooseEgg.

Reduce the Print Spooler vulnerability

Microsoft released a security update for the Print Spooler vulnerability exploited by GooseEgg on October 11, 2022 and updates for PrintNightmare vulnerabilities on June 8, 2021 and July 1, 2021. Customers who have not implemented these fixes yet are urged to do so as soon as possible for their organization’s security. In addition, since the Print Spooler service isn’t required for domain controller operations, Microsoft recommends disabling the service on domain controllers. Otherwise, users can install available Windows security updates for Print Spooler vulnerabilities on Windows domain controllers before member servers and workstations. To help identify domain controllers that have the Print Spooler service enabled, Microsoft Defender for Identity has a built-in security assessment that tracks the availability of Print Spooler services on domain controllers.

Be proactively defensive

• For customers, follow the credential hardening recommendations in our on-premises credential theft overview to defend against common credential theft techniques like LSASS access.
• Run Endpoint Detection and Response (EDR) in block mode so that Microsoft Defender for Endpoint can block malicious artifacts, even when your non-Microsoft antivirus does not detect the threat or when Microsoft Defender Antivirus is running in passive mode. EDR in block mode works behind the scenes to remediate malicious artifacts that are detected post-breach.    
• Configure investigation and remediation in full automated mode to let Microsoft Defender for Endpoint take immediate action on alerts to resolve breaches, significantly reducing alert volume. 
• Turn on cloud-delivered protection in Microsoft Defender Antivirus, or the equivalent for your antivirus product, to cover rapidly evolving attacker tools and techniques. Cloud-based machine learning protections block a majority of new and unknown variants.

Microsoft Defender XDR customers can turn on the following attack surface reduction rule to prevent common attack techniques used for GooseEgg. Microsoft Defender XDR detects the GooseEgg tool and raises an alert upon detection of attempts to exploit Print Spooler vulnerabilities regardless of whether the device has been patched.

•  Block credential stealing from the Windows local security authority subsystem (lsass.exe)

Detecting, hunting, and responding to GooseEgg

Microsoft Defender XDR detections

Microsoft Defender Antivirus

Microsoft Defender Antivirus detects threat components as the following malware:

• HackTool:Win64/GooseEgg

Microsoft Defender for Endpoint

The following alerts might also indicate threat activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Possible exploitation of CVE-2021-34527
• Possible source of PrintNightmare exploitation
• Possible target of PrintNightmare exploitation attempt
• Potential elevation of privilege using print filter pipeline service
• Suspicious behavior by spoolsv.exe
• Forest Blizzard Actor activity detected

Microsoft Defender for Identity

The following alerts might also indicate threat activity related to this threat. Note, however, that these alerts can be also triggered by unrelated threat activity.

• Suspected Windows Print Spooler service exploitation attempt (CVE-2021-34527 exploitation)

Threat intelligence reports

Microsoft customers can use the following reports in Microsoft products to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection information, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments.

Microsoft Defender Threat Intelligence

• Actor Profile: Forest Blizzard
• Abuse of Windows Print Spooler for privilege escalation and persistence

Hunting queries

Microsoft Sentinel

Microsoft Sentinel customers can use the TI Mapping analytics (a series of analytics all prefixed with ‘TI map’) to automatically match the malicious domain indicators mentioned in this blog post with data in their workspace. If the TI Map analytics are not currently deployed, customers can install the Threat Intelligence solution from the Microsoft Sentinel Content Hub to have the analytics rule deployed in their Sentinel workspace. More details on the Content Hub can be found here:  https://learn.microsoft.com/azure/sentinel/sentinel-solutions-deploy.

Hunt for filenames, file extensions in ProgramData folder and file hash

let filenames = dynamic(["execute.bat","doit.bat","servtask.bat"]);
DeviceFileEvents
  | where TimeGenerated > ago(60d) // change the duration according to your requirement
  | where ActionType == "FileCreated"
  | where FolderPath == "C:\\ProgramData\\"
  | where FileName in~ (filenames) or FileName endswith ".save" or FileName endswith ".zip" or ( FileName startswith "wayzgoose" and FileName endswith ".dll") or SHA256 == "7d51e5cc51c43da5deae5fbc2dce9b85c0656c465bb25ab6bd063a503c1806a9" // hash value of execute.bat/doit.bat/servtask.bat
  | project TimeGenerated, DeviceId, DeviceName, ActionType, FolderPath, FileName, InitiatingProcessAccountName,InitiatingProcessAccountUpn

Hunt for processes creating scheduled task creation

DeviceProcessEvents
| where TimeGenerated > ago(60d) // change the duration according to your requirement
| where InitiatingProcessSHA256 == "6b311c0a977d21e772ac4e99762234da852bbf84293386fbe78622a96c0b052f" or SHA256 == "6b311c0a977d21e772ac4e99762234da852bbf84293386fbe78622a96c0b052f" //hash value of justice.exe
or InitiatingProcessSHA256 == "c60ead92cd376b689d1b4450f2578b36ea0bf64f3963cfa5546279fa4424c2a5" or SHA256 == "c60ead92cd376b689d1b4450f2578b36ea0bf64f3963cfa5546279fa4424c2a5" //hash value of DefragmentSrv.exe
or ProcessCommandLine contains "schtasks /Create /RU SYSTEM /TN \\Microsoft\\Windows\\WinSrv /TR C:\\ProgramData\\servtask.bat /SC MINUTE" or
   ProcessCommandLine contains "schtasks /Create /RU SYSTEM /TN \\Microsoft\\Windows\\WinSrv /TR C:\\ProgramData\\execute.bat /SC MINUTE" or
   ProcessCommandLine contains "schtasks /Create /RU SYSTEM /TN \\Microsoft\\Windows\\WinSrv /TR C:\\ProgramData\\doit.bat /SC MINUTE" or
   ProcessCommandLine contains "schtasks /DELETE /F /TN \\Microsoft\\Windows\\WinSrv" or
   InitiatingProcessCommandLine contains "schtasks /Create /RU SYSTEM /TN \\Microsoft\\Windows\\WinSrv /TR C:\\ProgramData\\servtask.bat /SC MINUTE" or
   InitiatingProcessCommandLine contains "schtasks /Create /RU SYSTEM /TN \\Microsoft\\Windows\\WinSrv /TR C:\\ProgramData\\execute.bat /SC MINUTE" or
   InitiatingProcessCommandLine contains "schtasks /Create /RU SYSTEM /TN \\Microsoft\\Windows\\WinSrv /TR C:\\ProgramData\\doit.bat /SC MINUTE" or
   InitiatingProcessCommandLine contains "schtasks /DELETE /F /TN \\Microsoft\\Windows\\WinSrv"
| project TimeGenerated, AccountName,AccountUpn,ActionType, DeviceId, DeviceName,FolderPath, FileName

Hunt for JavaScript constrained file

DeviceFileEvents
  | where TimeGenerated > ago(60d) // change the duration according to your requirement
  | where ActionType == "FileCreated"
  | where FolderPath startswith "C:\\Windows\\System32\\DriverStore\\FileRepository\\"
  | where FileName endswith ".js" or FileName == "MPDW-constraints.js"

Hunt for creation of registry key / value events

DeviceRegistryEvents
  | where TimeGenerated > ago(60d) // change the duration according to your requirement
  | where ActionType == "RegistryValueSet"
  | where RegistryKey contains "HKEY_CURRENT_USER\\Software\\Classes\\CLSID\\{026CC6D7-34B2-33D5-B551-CA31EB6CE345}\\Server"
  | where RegistryValueName has "(Default)"
  | where RegistryValueData has "wayzgoose.dll" or RegistryValueData contains ".dll"

 Hunt for custom protocol handler

DeviceRegistryEvents
  | where TimeGenerated > ago(60d) // change the duration according to your requirement
  | where ActionType == "RegistryValueSet"
  | where RegistryKey contains "HKEY_CURRENT_USER\\Software\\Classes\\PROTOCOLS\\Handler\\rogue"
  | where RegistryValueName has "CLSID"
  | where RegistryValueData contains "{026CC6D7-34B2-33D5-B551-CA31EB6CE345}"

Indicators of compromise

Batch script artifacts:

• execute.bat
• doit.bat
• servtask.bat
• 7d51e5cc51c43da5deae5fbc2dce9b85c0656c465bb25ab6bd063a503c1806a9

GooseEgg artifacts:

• justice.pdb
• wayzgoose.pdb

References

• https://media.defense.gov/2021/Jul/01/2002753896/-1/-1/1/CSA_GRU_GLOBAL_BRUTE_FORCE_CAMPAIGN_UOO158036-21.PDF
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-34527
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-1675
• https://www.cisa.gov/news-events/cybersecurity-advisories/aa22-074a

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn at https://www.linkedin.com/showcase/microsoft-threat-intelligence, and on X (formerly Twitter) at https://twitter.com/MsftSecIntel.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast: https://thecyberwire.com/podcasts/microsoft-threat-intelligence.

The post Analyzing Forest Blizzard’s custom post-compromise tool for exploiting CVE-2022-38028 to obtain credentials appeared first on Microsoft Security Blog.

Microsoft Incident Response

Strengthen your security with an end-to-end portfolio of proactive and reactive cybersecurity incident response services.

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One click opens the door to a threat actor

We know that 50% of Microsoft cybersecurity recovery engagements relate to ransomware,² and 61% of all breaches involve credentials.³ Identity attacks continue to be a challenge for businesses because humans continue to be a central risk vector in social engineering identity attacks. People click links without thinking. Too often, users open attachments by habit, thereby opening the door to threat actors. Even when employees recognize credential harvesting attempts, they’re often still susceptible to drive-by URL attacks. And teams focused on incident response are often disconnected from teams that manage corporate identities. In this incident, one click on a malicious link led a large customer to reach out to Microsoft Incident Response for help.

Figure 1. Diagram of a threat actor’s malware moving through the network.

The malicious link the employee clicked infected their device with Qakbot. Qakbot is a modular malware that has been evolving for more than a decade. It’s a multipurpose malware that unfortunately gives attackers a wide range of capabilities. Once the identity-focused threat actor had established multiple avenues of persistence in the network and seemed to be preparing to deploy ransomware, the customer’s administrators and security operations staff were overwhelmed with tactical recovery and containment. That’s when they called Microsoft.

Your first call before, during, and after a cybersecurity incident

Microsoft Incident Response stepped in and deployed Microsoft Defender for Identity—a cloud-based security solution that helps detect and respond to identity-related threats. Bringing identity monitoring into incident response early helped an overwhelmed security operations team regain control. This first step helped to identify the scope of the incident and impacted accounts, take action to protect critical infrastructure, and work on evicting the threat actor. Then, by leveraging Microsoft Defender for Endpoint alongside Defender for Identity, Microsoft Incident Response was able to trace the threat actor’s movements and disrupt their attempts to use compromised accounts to reenter the environment. And once the tactical containment was complete and full administrative control over the environment was restored, Microsoft Incident Response worked with the customer to move forward to build better resiliency to help prevent future cyberattacks. More information about the incident and remediation details can be found on our technical post titled “Follow the Breadcrumbs with Microsoft Incident Response and Microsoft Defender for Identity: Working Together to Fight Identity-Based Attacks.”

Strengthen your identity posture with defense in depth

We know protecting user identities can help prevent incidents before they happen. But that protection can take many forms. Multiple, collaborative layers of defense—or defense in depth—can help build up protection so no single control must shoulder the entire defense. These layers include multifactor authentication, conditional access rules, mobile device and endpoint protection policies, and even new tools—like Microsoft Copilot for Security. Defense in depth can help prevent many cyberattacks—or at least make them difficult to execute—through the implementation and maintenance of layers of basic security controls.

In a recent Cyberattack Series blog post and report, we go more in depth on how to protect credentials against social engineering attacks. The cyberattack series case involved Octo Tempest—a highly active cyberthreat actor group which utilizes varying social engineering campaigns with the goal of financial extortion across many business sectors through means of data exfiltration and ransomware. Octo Tempest compromised a customer with a targeted phishing and smishing (text-based phishing) attack. That customer then reached out to Microsoft Incident Response for help to contain, evict, and detect any further threats. By collaborating closely with the victim organization’s IT and security teams, the compromised systems were isolated and contained. Throughout the entire process, effective communication and coordination between the incident response team and the affected organization is crucial. The team provides regular updates on their progress, shares threat intelligence, and offers guidance on remediation and prevention strategies. By working together seamlessly, the incident response team and the affected organization can mitigate the immediate cyberthreat, eradicate the cyberattacker’s presence, and strengthen the organization’s defenses against future cyberattacks.

Honeytokens: A sweet way to defend against identity-based attacks

Another layer of protection for user identities is the decoy account. These accounts are set up expressly to lure attackers, diverting their attention away from real targets and harmful activities—like accessing sensitive resources or escalating privileges. The decoy accounts are called honeytokens, and they can provide security teams with a unique opportunity to detect, deflect, or study attempted identity attacks. The best honeytokens are existing accounts with histories that can help hide their true nature. Honeytokens can also be a great way to monitor in-progress attacks, helping to discover where attackers are coming from and where they may be positioned in the network. For more detailed instructions on how to tag an account as a honeytoken and best practices for honeytoken use, read our tech community post titled “Deceptive defense: best practices for identity based honeytokens in Microsoft Defender for Identity.”

Working together to build better resilience

Microsoft Incident Response is the first call for customers who want to access dedicated experts before, during, and after any cybersecurity incident. With on-site and remote assistance on a global scale, unprecedented access to product engineering, and the depth and breadth of Microsoft Threat Intelligence, it encompasses both proactive and reactive incident response services. Collaboration is key. Microsoft Incident Response works with the tools and teams available to support incident response—like Defender for Identity, Defender for Endpoint, and now Copilot for Security—to defend against identity-based attacks, together. And that collaboration helps ensure better outcomes for customers. Learn more about the Microsoft Incident Response proactive and reactive response services or see it in action in the fourth installment of our ongoing Cyberattack Series.

To learn more about Microsoft Security solutions, visit our website. Bookmark the Security blog to keep up with our expert coverage on security matters. Also, follow us on LinkedIn (Microsoft Security) and X (@MSFTSecurity) for the latest news and updates on cybersecurity.

¹Microsoft Digital Defense Report, Microsoft. 2023.

²Microsoft Digital Defense Report, Microsoft. 2022.

³2023 Data Breach Investigations Report, Verizon.

⁴Microsoft Entra: 5 identity priorities for 2023, Joy Chik. January 9, 2023.

The post How Microsoft Incident Response and Microsoft Defender for Identity work together to detect and respond to cyberthreats appeared first on Microsoft Security Blog.

Octo Tempest is a financially motivated collective of native English-speaking threat actors known for launching wide-ranging campaigns that prominently feature adversary-in-the-middle (AiTM) techniques, social engineering, and SIM swapping capabilities. Octo Tempest, which overlaps with research associated with 0ktapus, Scattered Spider, and UNC3944, was initially seen in early 2022, targeting mobile telecommunications and business process outsourcing organizations to initiate phone number ports (also known as SIM swaps). Octo Tempest monetized their intrusions in 2022 by selling SIM swaps to other criminals and performing account takeovers of high-net-worth individuals to steal their cryptocurrency.

Building on their initial success, Octo Tempest harnessed their experience and acquired data to progressively advance their motives, targeting, and techniques, adopting an increasingly aggressive approach. In late 2022 to early 2023, Octo Tempest expanded their targeting to include cable telecommunications, email, and technology organizations. During this period, Octo Tempest started monetizing intrusions by extorting victim organizations for data stolen during their intrusion operations and in some cases even resorting to physical threats.

In mid-2023, Octo Tempest became an affiliate of ALPHV/BlackCat, a human-operated ransomware as a service (RaaS) operation, and initial victims were extorted for data theft (with no ransomware deployment) using ALPHV Collections leak site. This is notable in that, historically, Eastern European ransomware groups refused to do business with native English-speaking criminals. By June 2023, Octo Tempest started deploying ALPHV/BlackCat ransomware payloads (both Windows and Linux versions) to victims and lately has focused their deployments primarily on VMWare ESXi servers. Octo Tempest progressively broadened the scope of industries targeted for extortion, including natural resources, gaming, hospitality, consumer products, retail, managed service providers, manufacturing, law, technology, and financial services.  

In recent campaigns, we observed Octo Tempest leverage a diverse array of TTPs to navigate complex hybrid environments, exfiltrate sensitive data, and encrypt data. Octo Tempest leverages tradecraft that many organizations don’t have in their typical threat models, such as SMS phishing, SIM swapping, and advanced social engineering techniques. This blog post aims to provide organizations with an insight into Octo Tempest’s tradecraft by detailing the fluidity of their operations and to offer organizations defensive mechanisms to thwart the highly motivated financial cybercriminal group.

Analysis 

The well-organized, prolific nature of Octo Tempest’s attacks is indicative of extensive technical depth and multiple hands-on-keyboard operators. The succeeding sections cover the wide range of TTPs we observed being used by Octo Tempest.

Initial access 

Social engineering with a twist

Octo Tempest commonly launches social engineering attacks targeting technical administrators, such as support and help desk personnel, who have permissions that could enable the threat actor to gain initial access to accounts. The threat actor performs research on the organization and identifies targets to effectively impersonate victims, mimicking idiolect on phone calls and understanding personal identifiable information to trick technical administrators into performing password resets and resetting multifactor authentication (MFA) methods. Octo Tempest has also been observed impersonating newly hired employees in these attempts to blend into normal on-hire processes.

Octo Tempest primarily gains initial access to an organization using one of several methods:

• Social engineering
  • Calling an employee and socially engineering the user to either:
    • Install a Remote Monitoring and Management (RMM) utility
    • Navigate to a site configured with a fake login portal using an adversary-in-the-middle toolkit
    • Remove their FIDO2 token
  • Calling an organization’s help desk and socially engineering the help desk to reset the user’s password and/or change/add a multi-factor authentication token/factor
• Purchasing an employee’s credentials and/or session token(s) on a criminal underground market
• SMS phishing employee phone numbers with a link to a site configured with a fake login portal using an adversary-in-the-middle toolkit
• Using the employee’s pre-existing access to mobile telecommunications and business process outsourcing organizations to initiate a SIM swap or to set up call number forwarding on an employee’s phone number. Octo Tempest will initiate a self-service password reset of the user’s account once they have gained control of the employee’s phone number.

In rare instances, Octo Tempest resorts to fear-mongering tactics, targeting specific individuals through phone calls and texts. These actors use personal information, such as home addresses and family names, along with physical threats to coerce victims into sharing credentials for corporate access.

Reconnaissance and discovery 

Crossing borders for identity, architecture, and controls enumeration

In the early stage of their attacks, Octo Tempest performs various enumeration and information gathering actions to pursue advanced access in targeted environments and abuses legitimate channels for follow-on actions later in the attack sequence. Initial bulk-export of users, groups, and device information is closely followed by enumerating data and resources readily available to the user’s profile within virtual desktop infrastructure or enterprise-hosted resources. 

Frequently, Octo Tempest uses their access to carry out broad searches across knowledge repositories to identify documents related to network architecture, employee onboarding, remote access methods, password policies, and credential vaults.

Octo Tempest then performs exploration through multi-cloud environments enumerating access and resources across cloud environments, code repositories, server and backup management infrastructure, and others. In this stage, the threat actor validates access, enumerates databases and storage containers, and plans footholds to aid further phases of the attack.

Additional tradecraft and techniques:

• PingCastle and ADRecon to perform reconnaissance of Active Directory 
• Advanced IP Scanner to probe victim networks
• Govmomi Go library to enumerate vCenter APIs 
• PureStorage FlashArray PowerShell module to enumerate storage arrays 
• AAD bulk downloads of user, groups, and devices

Privilege escalation and credential access

Octo Tempest commonly elevates their privileges within an organization through the following techniques:

• Using their pre-existing access to mobile telecommunications and business process outsourcing organizations to initiate a SIM swap or to set up call number forwarding on an employee’s phone number. Octo Tempest will initiate a self-service password reset of the user’s account once they have gained control of the employee’s phone number.
• Social engineering – calling an organization’s help desk and socially engineering the help desk to reset an administrator’s password and/or change/add a multi-factor authentication token/factor

Further masquerading and collection for escalation

Octo Tempest employs an advanced social engineering strategy for privilege escalation, harnessing stolen password policy procedures, bulk downloads of user, group, and role exports, and their familiarity with the target organizations procedures. The actor’s privilege escalation tactics often rely on building trust through various means, such as leveraging possession of compromised accounts and demonstrating an understanding of the organization’s procedures. In some cases, they go as far as bypassing password reset procedures by using a compromised manager’s account to approve their requests.

Octo Tempest continually seeks to collect additional credentials across all planes of access. Using open-source tooling like Jercretz and TruffleHog, the threat actor automates the identification of plaintext keys, secrets, and credentials across code repositories for further use.

Additional tradecraft and techniques:

• Modifying access policies or using MicroBurst to gain access to credential stores
• Using open-source tooling: Mimikatz, Hekatomb, Lazagne, gosecretsdump, smbpasswd.py, LinPEAS, ADFSDump
• Using VMAccess Extension to reset passwords or modify configurations of Azure VMs
• Creating snapshots virtual domain controller disks to download and extract NTDS.dit
• Assignment of User Access Administrator role to grant Tenant Root Group management scope

Defense evasion

Security product arsenal sabotage

Octo Tempest compromises security personnel accounts within victim organizations to turn off security products and features and attempt to evade detection throughout their compromise. Using compromised accounts, the threat actor leverages EDR and device management technologies to allow malicious tooling, deploy RMM software, remove or impair security products, data theft of sensitive files (e.g. files with credentials, signal messaging databases, etc.), and deploy malicious payloads.

To prevent identification of security product manipulation and suppress alerts or notifications of changes, Octo Tempest modifies the security staff mailbox rules to automatically delete emails from vendors that may raise the target’s suspicion of their activities.

Additional tradecraft and techniques:

• Using open-source tooling like privacy.sexy framework to disable security products
• Enrolling actor-controlled devices into device management software to bypass controls
• Configuring trusted locations in Conditional Access Policies to expand access capabilities
• Replaying harvested tokens with satisfied MFA claims to bypass MFA

Persistence 

Sustained intrusion with identities and open-source tools

Octo Tempest leverages publicly available security tools to establish persistence within victim organizations, largely using account manipulation techniques and implants on hosts. For identity-based persistence, Octo Tempest targets federated identity providers using tools like AADInternals to federate existing domains, or spoof legitimate domains by adding and then federating new domains. The threat actor then abuses this federation to generate forged valid security assertion markup language (SAML) tokens for any user of the target tenant with claims that have MFA satisfied, a technique known as Golden SAML. Similar techniques have also been observed using Okta as their source of truth identity provider, leveraging Okta Org2Org functionality to impersonate any desired user account.

To maintain access to endpoints, Octo Tempest installs a wide array of legitimate RMM tools and makes required network modifications to enable access. The usage of reverse shells is seen across Octo Tempest intrusions on both Windows and Linux endpoints. These reverse shells commonly initiate connections to the same attacker infrastructure that deployed the RMM tools.

A unique technique Octo Tempest uses is compromising VMware ESXi infrastructure, installing the open-source Linux backdoor Bedevil, and then launching VMware Python scripts to run arbitrary commands against housed virtual machines.

Additional tradecraft and techniques:

• Usage of open-source tooling: ScreenConnect, FleetDeck, AnyDesk, RustDesk, Splashtop, Pulseway, TightVNC, LummaC2, Level.io, Mesh, TacticalRMM, Tailscale, Ngrok, WsTunnel, Rsocx, and Socat
• Deployment of Azure virtual machines to enable remote access via RMM installation or modification to existing resources via Azure serial console
• Addition of MFA methods to existing users
• Usage of the third-party tunneling tool Twingate, which leverages Azure Container instances as a private connector (without public network exposure)

Actions on objectives

Common trifecta: Data theft, extortion, and ransomware

The goal of Octo Tempest remains financially motivated, but the monetization techniques observed across industries vary between cryptocurrency theft and data exfiltration for extortion and ransomware deployment.

Like in most cyberattacks, data theft largely depends on the data readily available to the threat actor. Octo Tempest accesses data from code repositories, large document management and storage systems, including SharePoint, SQL databases, cloud storage blobs/buckets, and email, using legitimate management clients such as DBeaver, MongoDB Compass, Azure SQL Query Editor, and Cerebrata for the purpose of connection and collection. After data harvesting, the threat actor employs anonymous file-hosting services, including GoFile.io, shz.al, StorjShare, Temp.sh, MegaSync, Paste.ee, Backblaze, and AWS S3 buckets for data exfiltration.

Octo Tempest employs a unique technique using the data movement platform Azure Data Factory and automated pipelines to extract data to external actor hosted Secure File Transfer Protocol (SFTP) servers, aiming to blend in with typical big data operations. Additionally, the threat actor commonly registers legitimate Microsoft 365 backup solutions such as Veeam, AFI Backup, and CommVault to export the contents of SharePoint document libraries and expedite data exfiltration.

Ransomware deployment closely follows data theft objectives. This activity targets both Windows and Unix/Linux endpoints and VMware hypervisors using a variant of ALPHV/BlackCat. Encryption at the hypervisor level has shown significant impact to organizations, making recovery efforts difficult post-encryption.

Octo Tempest frequently communicates with target organizations and their personnel directly after encryption to negotiate or extort the ransom—providing “proof of life” through samples of exfiltrated data. Many of these communications have been leaked publicly, causing significant reputational damage to affected organizations.

Additional tradecraft and techniques:

• Use of the third-party services like FiveTran to extract copies of high-value service databases, such as SalesForce and ZenDesk, using API connectors
• Exfiltration of mailbox PST files and mail forwarding to external mailboxes

Recommendations

Hunting methodology

Octo Tempest’s utilization of social engineering, living-off-the land techniques, and diverse toolsets could make hunting slightly unorthodox. Following these general guidelines alongside robust deconfliction with legitimate users will surface their activity:

Identity

• Understand authentication flows in the environment.
• Centralize visibility of administrative changes in the environment into a single pane of glass.
• Scrutinize all user and sign-in risk detections for any administrator within the timeframe. Common alerts that are surfaced during an Octo Tempest intrusion include (but not limited to): Impossible Travel, Unfamiliar Sign-in Properties, and Anomalous Token
• Review the coverage of Conditional Access policies; scrutinize the use of trusted locations and exclusions.
• Review all existing and new custom domains in the tenant, and their federation settings.
• Scrutinize administrator groups, roles, and privileges for recent modification.
• Review recently created Microsoft Entra ID users and registered device identities.
• Look for any anomalous pivots into organizational apps that may hold sensitive data, such as Microsoft SharePoint and OneDrive.

Azure

• Leverage and continuously monitor Defender for Cloud for Azure Workloads, providing a wealth of information around unauthorized resource access.
• Review Azure role-based access control (RBAC) definitions across the management group, subscription, resource group and resource structure.
• Review the public network exposure of resources and revoke any unauthorized modifications.
• Review both data plane and management plane access control for all critical workloads such as those that hold credentials and organizational data, like Key Vaults, storage accounts, and database resources.
• Tightly control access to identity workloads that issue access organizational resources such as Active Directory Domain Controllers.
• Review the Azure Activity log for anomalous modification of resources.

Endpoints

• Look for recent additions to the indicators or exclusions of the EDR solution in place at the organization.
• Review any generation of offboarding scripts.
• Review access control within security products and EDR software suites.
• Scrutinize any tools used to manage endpoints (SCCM, Intune, etc.) and look for recent rule additions, packages, or deployments.
• Scrutinize use of remote administration tools across the environment, paying particular attention to recent installations regardless of whether they are used legitimately within the network already.
• Ensure monitoring at the network boundary is in place, that alerting is in place for connections with common anonymizing services and scrutinize the use of these services.

Defending against Octo Tempest activity

Align privilege in Microsoft Entra ID and Azure

Privileges spanning Microsoft Entra ID and Azure need to be holistically aligned, with purposeful design decisions to prevent unauthorized access to critical workloads. Reducing the number of users with permanently assigned critical roles is paramount to achieving this. Segregation of privilege between on-premises and cloud is also necessary to sever the ability to pivot within the environment.

It is highly recommended to implement Microsoft Entra Privileged Identity Management (PIM) as a central location for the management of both Microsoft Entra ID roles and Azure RBAC. For all critical roles, at minimum:

• Implement role assignments as eligible rather than permanent.
• Review and understand the role definition Actions and NotActions – ensure to select only the roles with actions that the user requires to do their role (least privileged access).
• Configure these roles to be time-bound, deactivating after a specific timeframe.
• Require users to perform MFA to elevate to the role.
• Optionally require users to provide justification or a ticket number upon elevation.
• Enable notifications for privileged role elevation to a subset of administrators.
• Utilize PIM Access Reviews to reduce standing access in the organization on a periodic basis.

Every organization is different and, therefore, roles will be classified differently in terms of their criticality. Consider the scope of impact those roles may have on downstream resources, services, or identities in the event of compromise. For help desk administrators specifically, ensure to scope privilege to exclude administrative operations over Global Administrators. Consider implementing segregation strategies such as Microsoft Entra ID Administrative Units to segment administrative access over the tenant. For identities that leverage cross-service roles such as those that service the Microsoft Security Stack, consider implementing additional service-based granular access control to restrict the use of sensitive functionality, like Live Response and modification of IOC allow lists.

Segment Azure landing zones

For organizations yet to begin or are early in their modernization journey, end-to-end guidance for cloud adoption is available through the Microsoft Azure Cloud Adoption Framework. Recommended practice and security are central pillars—Azure workloads are segregated into separate, tightly restricted areas known as landing zones. When deploying Active Directory in the cloud, it is advised to create a platform landing zone for identity—a dedicated subscription to hold all Identity-related resources such as Domain Controller VM resources. Employ least privilege across this landing zone with the aforementioned privilege and PIM guidance for Azure RBAC.

Implement Conditional Access policies and authentication methods

TTPs outlined in this blog leverage strategies to evade multifactor authentication defenses. However, it is still strongly recommended to practice basic security hygiene by implementing a baseline set of Conditional Access policies:

• Require multifactor authentication for all privileged roles with the use of authentication strengths to enforce phish-resistant MFA methods such as FIDO2 security keys
• Require phishing-resistant multifactor authentication for administrators
• Enforce MFA registration from trusted locations from a device that also meets organizational requirements with Intune device compliance policies
• User and sign-in risk policies for signals associated to Microsoft Entra ID Protection

Organizations are recommended to keep their policies as simple as possible. Implementing complex policies might inhibit the ability to respond to threats at a rapid pace or allow threat actors to leverage misconfigurations within the environment.

Develop and maintain a user education strategy

An organization’s ability to protect itself against cyberattacks is only as strong as its people—it is imperative to put in place an end-to-end cybersecurity strategy highlighting the importance of ongoing user education and awareness. Targeted education and periodic security awareness campaigns around common cyber threats and attack vectors such as phishing and social engineering not only for users that hold administrative privilege in the organization, but the wider user base is crucial. A well-maintained incident response plan should be developed and refined to enable organizations to respond to unexpected cybersecurity events and rapidly regain positive control.

Use out-of-band communication channels

Octo Tempest has been observed joining, recording, and transcribing calls using tools such as OtterAI, and sending messages via Slack, Zoom, and Microsoft Teams, taunting and threatening targets, organizations, defenders, and gaining insights into incident response operations/planning. Using out-of-band communication channels is strongly encouraged when dealing with this threat actor.

Detections

Microsoft 365 Defender

Microsoft 365 Defender is becoming Microsoft Defender XDR. Learn more.

NOTE: Several tools mentioned throughout this blog are remote administrator tools that have been utilized by Octo Tempest to maintain persistence. While these tools are abused by threat actors, they can have legitimate use cases by normal users, and are updated on a frequent basis. Microsoft recommends monitoring their use within the environment, and when they are identified, defenders take the necessary steps for deconfliction to verify their use.

Microsoft Defender Antivirus

Microsoft Defender Antivirus detects this threat as the following malware:

• HackTool:Win32/Mimikatz
• HackTool:Win64/Mimikatz
• Behavior:Win32/BlackCatExec
• Ransom:Win32/Blackcat
• Ransom:Linux/BlackCat
• Behavior:Win32/BlackCat
• Ransom:Win64/BlackCat

Turning on tamper protection, which is part of built-in protection, prevents attackers from stopping security services.

Microsoft Defender for Endpoint

The following Microsoft Defender for Endpoint alerts can indicate associated threat activity:

• Octo Tempest activity group

The following alerts might also indicate threat activity related to this threat. Note, however, that these alerts can also be triggered by unrelated threat activity.

• Suspicious usage of remote management software
• Mimikatz credential theft tool
• BlackCat ransomware
• Activity linked to BlackCat ransomware
• Tampering activity typical to ransomware attacks
• Possible hands-on-keyboard pre-ransom activity

Microsoft Defender for Cloud Apps

Using Microsoft Defender for Cloud Apps connectors, Microsoft 365 Defender raises AitM-related alerts in multiple scenarios. For Microsoft Entra ID customers using Microsoft Edge, attempts by attackers to replay session cookies to access cloud applications are detected by Microsoft 365 Defender through Defender for Cloud Apps connectors for Microsoft Office 365 and Azure. In such scenarios, Microsoft 365 Defender raises the following alerts:

• Backdoor creation using AADInternals tool
• Suspicious domain added to Microsoft Entra ID
• Suspicious domain trust modification following risky sign-in
• User compromised via a known AitM phishing kit
• User compromised in AiTM phishing attack
• Suspicious email deletion activity

Similarly, the connector for Okta raises the following alerts:

• Suspicious Okta account enumeration
• Possible AiTM phishing attempt in Okta

Microsoft Defender for Identity

Microsoft Defender for Identity raises the following alerts for TTPs used by Octo Tempest such as NTDS stealing and Active Directory reconnaissance:

• Account enumeration reconnaissance
• Network-mapping reconnaissance (DNS)
• User and IP address reconnaissance (SMB)
• User and Group membership reconnaissance (SAMR)
• Suspected DCSync attack (replication of directory services)
• Suspected AD FS DKM key read
• Data exfiltration over SMB

Microsoft Defender for Cloud

The following Microsoft Defender for Cloud alerts relate to TTPs used by Octo Tempest. Note, however, that these alerts can also be triggered by unrelated threat activity.

• MicroBurst exploitation toolkit used to enumerate resources in your subscriptions
• MicroBurst exploitation toolkit used to execute code on your virtual machine
• MicroBurst exploitation toolkit used to extract keys from your Azure key vaults
• MicroBurst exploitation toolkit used to extract keys to your storage accounts
• Suspicious Azure role assignment detected
• Suspicious elevate access operation (Preview)
• Suspicious invocation of a high-risk ‘Initial Access’ operation detected (Preview)
• Suspicious invocation of a high-risk ‘Credential Access’ operation detected (Preview)
• Suspicious invocation of a high-risk ‘Data Collection’ operation detected (Preview)
• Suspicious invocation of a high-risk ‘Execution’ operation detected (Preview)
• Suspicious invocation of a high-risk ‘Impact’ operation detected (Preview)
• Suspicious invocation of a high-risk ‘Lateral Movement’ operation detected (Preview)
• Unusual user password reset in your virtual machine
• Suspicious usage of VMAccess extension was detected on your virtual machines (Preview)
• Suspicious usage of multiple monitoring or data collection extensions was detected on your virtual machines (Preview)
• Run Command with a suspicious script was detected on your virtual machine (Preview)
• Suspicious Run Command usage was detected on your virtual machine (Preview)
• Suspicious unauthorized Run Command usage was detected on your virtual machine (Preview)

Microsoft Sentinel

Microsoft Sentinel customers can use the following Microsoft Sentinel Analytics template to identify potential AitM phishing attempts:

• Possible AitM Phishing Attempt Against Azure AD

This detection uses signals from Microsoft Entra ID Identity Protection and looks for successful sign-ins that have been flagged as high risk. It combines this with data from web proxy services, such as ZScaler, to identify where users might have connected to the source of those sign-ins immediately prior. This can indicate a user interacting with an AitM phishing site and having their session hijacked. This detection uses the Advanced Security Information Model (ASIM) Web Session schema. Refer to this article for more details on the schema and its requirements. 

Threat intelligence reports

Microsoft customers can use the following reports in Microsoft products to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection info, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments.

Microsoft Defender Threat Intelligence

• Octo Tempest
• Octo Tempest uses social engineering and AADInternals to compromise cloud identities

Microsoft 365 Defender Threat analytics  

• Actor profile: Octo Tempest
• Threat insights: Octo Tempest uses social engineering and AADInternals to compromise cloud identities

Hunting queries

Microsoft Sentinel

Microsoft Sentinel customers can use the TI Mapping analytics (a series of analytics all prefixed with ‘TI map’) to automatically match the malicious domain indicators mentioned in this blog post with data in their workspace. If the TI Map analytics are not currently deployed, customers can install the Threat Intelligence solution from the Microsoft Sentinel Content Hub to have the analytics rule deployed in their Sentinel workspace.

Microsoft Sentinel also has a range of detection and threat hunting content that customers can use to detect the post exploitation activity detailed in this blog in addition to Microsoft 365 Defender detections list above.

• Suspicious sign-in followed by MFA modification
• Account MFA modifications
• Okta SSO phishing detection
• Okta rare MFA operations
• Okta login from different locations
• Okta user password reset
• SharePointFileOperation via clientIP with previously unseen user agents
• SharePointFileOperation via devices with previously unseen user agents
• SharePointFileOperation via previously unseen IPs of risky ASN’s
• SharePointFileOperation via previously unseen IPs
• Anomalous AAD account manipulation
• New external user granted admin
• Anomolous sign-ins based on time
• New account added to admin group
• Authentication methods changed for privileged account
• Rare run command PowerShell script
• Azure NSG administrative operations
• Rare operations of create and update of snapshots
• AdFind usage
• Anomalous listing of storage keys
• Storage account key enumeration
• Potential Microsoft Security services tampering
• Potential Microsoft Defender tampering
• Office mail forwarding
• Multiple users Office mail forwarding

Further reading

Listen to Microsoft experts discuss Octo Tempest TTPs and activities on The Microsoft Threat Intelligence Podcast.

Visit this page for more blogs from Microsoft Incident Response.

For more security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on X (formerly Twitter) at https://twitter.com/MsftSecIntel.

November 1, 2023 update: Updated the Actions of objectives section to fix the list of anonymous file-hosting services used by Octo Tempest for data exfiltration, which incorrectly listed Sh.Azl. It has been corrected to shz.al.

The post Octo Tempest crosses boundaries to facilitate extortion, encryption, and destruction appeared first on Microsoft Security Blog.

Attackers compromise user accounts through numerous and diverse means, including techniques like credential dumping, keylogging, and brute-forcing. Poor credential hygiene could very quickly lead to the compromise of domain admin-level accounts, which could allow attackers to access domain resources and devices, and completely take over the network. Based on incidents analyzed by Microsoft, it can take only a single hop from the attacker’s initial access vector to compromise domain admin-level accounts. For instance, an attacker can target an over-privileged service account configured in an outdated and vulnerable internet-facing server.

Highly privileged user accounts are arguably the most important assets for attackers. Compromised domain admin-level accounts in environments that use traditional solutions provide attackers with access to Active Directory and could subvert traditional security mechanisms. In addition to compromising existing accounts, attackers have adopted the creation of additional dormant, highly privileged user accounts as persistence mechanisms.

Identifying and containing these compromised user accounts, therefore, prevents attacks from progressing, even if attackers gain initial access. This is why, as announced today, we added user containment to the automatic attack disruption capability in Microsoft Defender for Endpoint, a unique and innovative defense mechanism that stops human-operated attacks in their tracks. User containment prevents a compromised user account from accessing endpoints and other resources in the network, limiting attackers’ ability to move laterally regardless of the account’s Active Directory state or privilege level. It is automatically triggered by high-fidelity signals indicating that a compromised user account is being used in an ongoing attack. With user containment, even compromised domain admin accounts cannot help attackers access other devices in the network.

In this blog we will share our analysis of real-world incidents and demonstrate how automatic attack disruption protected our customers by containing compromised user accounts. We then explain how this capability fits in our automatic attack disruption strategy and how it works under the hood.

User containment stops Storm-1567 attack, prevents Akira ransomware encryption

In early June 2023, an industrial engineering organization was the target of a human-operated attack by an Akira ransomware operator tracked by Microsoft as Storm-1567. Akira is a ransomware strain first observed by Microsoft in March 2023 and has features common to other ransomware payloads like the use of ChaCha encryption algorithm, PowerShell, and Windows Management Instrumentation (WMI). Microsoft assesses that Akira is most likely a closed ransomware offering and not openly marketed as ransomware as a service.

In this attack, the threat actor leveraged devices that were not onboarded to Microsoft Defender for Endpoint for most of the attack stages, a defense evasion tactic we’ve seen in other attacks. While visibility by our endpoint solution could have blocked the attack earlier in the attack chain and helped to protect the organization’s devices much sooner, Defender for Endpoint nonetheless successfully prevented the ransomware stage, protecting all onboarded devices in the organization from getting encrypted.

Based on our analysis, after gaining access to the network, the threat actor started preparing to encrypt devices by scanning, attempting to tamper with security products, conducting lateral movement using Remote Desktop Protocol (RDP), and other anomalous activities. It should be noted that the activities were conducted on a Sunday evening, a time when SOC teams might be at a limited capacity. Most of these activities were done on Windows Server devices, including SQL Servers onboarded to Microsoft Defender for Endpoint. These activities were highly anomalous compared to routine activity in the customer’s network and therefore triggered multiple alerts.

Microsoft Defender for Endpoint’s next-generation protection capabilities detected and prevented several attacker activities, prompting the attackers to try tampering with the security product. However, tamper protection was enabled in the environment, so these attempts were not successful. Meanwhile, Microsoft 365 Defender correlated signals from multiple Defender products, identified the malicious activity, and incriminated – that is, determined as malicious with high confidence – the associated compromised assets, including a user account the attackers used.

Approximately half an hour after activity began, attackers leveraged the compromised user account and attempted to encrypt devices remotely via Server Message Block (SMB) protocol from a device not onboarded to Microsoft Defender for Endpoint. Because of the earlier incrimination, the compromised user account was contained, and the devices onboarded to Defender for Endpoint were protected from encryption attempts.

Later the same day, the attackers repeated the same malicious sequences by pivoting to other compromised user accounts, attempting to bypass attack disruption protection. Defender for Endpoint was again able to protect onboarded devices from encryption over the network. In this incident, automatic attack disruption’s ability to contain additional compromised user accounts demonstrated unique and innovative impact for endpoint and identity security, helping to protect all devices onboarded to Defender for Endpoint from the attack.    

User containment stops lateral movement in human-operated campaign

In early August 2023, Microsoft Defender for Endpoint automatically disrupted a human-operated attack early in the attack chain by containing the compromised user account prior to any impact, saving a medical research lab from what could have been a large-scale attack. The first indication of the attack was observed at roughly 4:00 AM local time on a Friday, when attackers, operating from a device not onboarded to Defender for Endpoint, initiated a remote password reset for the default domain administrator account. This account wasn’t active on any device onboarded to Microsoft Defender for Endpoint in the months prior to the intrusion. We infer that the account credentials were likely expired, and that the attackers found the stale password hashes belonging to the account by using commodity credential theft tools like Mimikatz on a device not-onboarded to Microsoft Defender for Endpoint. Expired credentials, while often not seen as a security risk, could still be abused and could allow attackers to update an account’s password.

Minutes after the administrator account password was reset, the attackers started scanning the network for accessible shares and enumerated other account and domain configurations using SMB-accessible services. This scan and all subsequent malicious activities originated from the same non-onboarded device and compromised administrator account.

Parallel to the network scan, the threat actor initiated an RDP session to a SQL Server, attempting to tamper with security products on the server and running a variety of credential theft and domain discovery tools.

At this point, the compromised administrator account was incriminated based on cumulative signals from the Defender for Endpoint-onboarded SQL server and the account’s anomalous activity. Automatic attack disruption was triggered and the compromised account was contained. All devices in the organization that supported the user containment feature immediately blocked SMB access from the compromised user account, stopping the discovery operations and preventing the possibility of subsequent lateral movement.

Following the initial containment of the attack through automatic attack disruption, the SOC was then able to take additional critical remediation actions to expand the scope of the disruption and evict the attackers from the network. This included terminating the attackers’ sessions on two compromised servers and disabling the compromised domain administrator account at the Active Directory-level.

While user containment is automatic for devices onboarded to Defender for Endpoint, this incident demonstrates the importance of active engagement of the SOC team after the automatic attack disruption action to fully evict the attackers from the environment. It also shows that onboarding devices to Microsoft Defender for Endpoint improves the overall capability to detect and disrupt attacks within the network sooner, before high-privileged user accounts are compromised.

In addition, as of September 2023, user containment also supports terminating active RDP sessions, in addition of blocking new attempted connections, a critical first step in evicting attackers from the network. Disabling compromised user accounts at the Active Directory-level is already supported by automatic attack disruption through integration with Defender for Identity. In this particular incident, the customer was not using Defender for Identity, but this case highlights the stronger defenses as a result of cross-domain visibility.

Protecting against compromised user accounts through automatic containment

As demonstrated by the incidents we described above, unlike commodity malware infection, human-operated attacks are driven by humans with hands-on-keyboard access to the network who make decisions at every stage of their attack. Attack patterns vary depending on what attackers find in the target network. Protecting against such highly skilled, profit-driven, and determined adversaries is not trivial. These attackers leverage key principles of on-premises Active Directory environments, which provide an active domain administrator account unlimited access to domain resources. Once attackers obtain accounts with sufficient privileges, they can conduct malicious activities like lateral movement or data access using legitimate administrative tools and protocols.

At Microsoft, we understand that to better defend our customers against such highly motivated attackers, a multi-layer defense approach must be used for an optimal security protection solution across endpoints and identities. More importantly, this solution should prioritize organization-wide protection, rather than protecting only a single endpoint. Motivated attackers search for security weaknesses and prioritize compromising unprotected devices. As a result, assuming that initial attack stages have occurred, with potentially at least a few compromised user accounts, is critical for developing security defenses for later attack stages. Using key assumptions and principles of on-premises Active Directory environments, a security-first mindset means limiting the access of even the most privileged user accounts to mitigate security risks.

The automatic attack disruption capability contains user accounts by creating a boundary between healthy onboarded devices and compromised user accounts and devices. It works in a decentralized nature: a containment policy distributed to all onboarded devices across the organization enables each Microsoft Defender for Endpoint client to protect the device against any compromised account, even an account belonging to the Domain Admins group.

This decentralized approach avoids some of the pitfalls of centralized manual or automatic controls, such as disabling an account in Active Directory, which possesses a single point of failure as it can be overridden by the attacker who may already have compromised domain controllers. The virtual security boundary set to contain the user is implemented by controls that were tailored to disrupt attacker activity during various attack stages, including lateral movement, credential theft, and impact such as remote encryption or deployment of ransomware payload. The actual set of controls triggered to contain a user might vary depending on the attack scenario and stage, and includes:

1. Sign-in restriction: This is the most aggressive control in containing a user account. When this control is triggered, devices will deny all or some types of sign-ins by a compromised account. This control takes effect immediately and is effective regardless of the account’s state (i.e., active or disabled) in the authority it belongs to. This control can block most attacker capabilities, but in cases where an attacker had already authenticated to device before a compromise was identified, the other controls might still be required to block the attack.
2. Intercepting SMB activity: Attack disruption can contain a user by denying inbound file system access from a remote origin, limiting the attacker’s ability to remotely steal or destroy valuable data. Notably, this control can prevent or limit ransomware encryption over SMB. It can also block lateral movement methods that include a payload being created on a remote device, including PsExec and similar tools.
3. Filtering RPC activity: Attack disruption can selectively restrict compromised users’ access to remote procedure call (RPC) interfaces that attackers often leverage during attacks. Attackers abuse RPC-based protocols for a variety of goals such credential theft (DCsync and DPAPI), privilege escalation (“PetitPotam”, Print Spooler), discovery (server & workstation services), and lateral movement (remote WMI, scheduled tasks, and services). Blocking such activities can contain an attack before the attacker gains a strong foothold in the network or can deny the ability to capitalize on such a foothold during the impact stage.
4. Disconnecting or terminating active sessions: In case a compromised account had already gained a foothold on the device, when attack disruption is triggered, it can disconnect or terminate sessions previously initiated by the account. This control differs from the others in this list as it’s effective against already compromised devices, protecting against any additional malicious activity by the attacker. Once a session is terminated, attackers are locked out of the device by the sign-in restriction control. This is specifically critical in stopping attacks earlier in the attack chain, disrupting and containing attacks before reaching impact stage.

The user containment capability is part of the existing protections provided by solutions within Microsoft 365 Defender. As we described in this blog, this capability correlates high-fidelity signals from multiple Defender products to incriminate malicious entities with high confidence and then immediately contain them to automatically disrupt ongoing attacks, including the pre-ransomware and encryption stages in human-operated attacks.

To benefit from this capability, organizations need only to onboard devices to Microsoft Defender for Endpoint. As more devices are onboarded, the scope of disruption is larger and the level of protection is higher. And as more Defender products are used in the organization, the visibility is wider and the effectiveness of the solution is greater. This also lowers the risk of attackers taking advantage of unprotected devices as launch pads for attacks.

Automatic attack disruption represents an innovative solution designed to increase defenses against the increasingly more sophisticated threat of hands-on-keyboard attacks, especially human-operated ransomware. This capability is informed by threat intelligence and insights from investigations and analysis of threats and actors in the cybercrime economy, and reflects our commitment to provide industry-best protections for our customers.

Edan Zwick, Amir Kutcher, Charles-Edouard Bettan, Yair Tsarfaty, Noam Hadash

Further reading

Learn how Microsoft Defender for Endpoint stops human-operated attacks.

For more information, read our documentation on the automatic attack disruption capability.

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us at https://twitter.com/MsftSecIntel.

The post Automatic disruption of human-operated attacks through containment of compromised user accounts appeared first on Microsoft Security Blog.

In cases where Peach Sandstorm successfully authenticated to an account, Microsoft observed the group using a combination of publicly available and custom tools for discovery, persistence, and lateral movement. In a small number of intrusions, Peach Sandstorm was observed exfiltrating data from the compromised environment.

Given the volume of activity, ongoing attempts to access targets of interest, and risks associated with post-compromise activity, Microsoft is reporting on this campaign to raise awareness of recent Peach Sandstorm tradecraft and empower organizations to harden their attack surfaces and defend against this activity. As with any observed nation state actor activity, Microsoft directly notifies customers that have been targeted or compromised by Peach Sandstorm and provides them with the information they need to secure their accounts.

Who is Peach Sandstorm?

Peach Sandstorm is an Iranian nation-state group known to target organizations in multiple countries. In past attacks, Peach Sandstorm has pursued targets in the aviation, construction, defense, education, energy, financial services, healthcare, government, satellite, and telecommunications sectors. Activity that Microsoft attributes to Peach Sandstorm overlaps with public reporting on groups known as APT33, Elfin, and Refined Kitten.

Throughout 2023, Peach Sandstorm has consistently demonstrated interest in organizations in the satellite, defense, and to a lesser extent, pharmaceutical sectors.  In the initial phase of this campaign, Peach Sandstorm conducted password spray campaigns against thousands of organizations across several sectors and geographies. While Microsoft observed several organizations previously targeted by Peach Sandstorm, the volume of activity and range of organizations suggests that at least a subset of the initial activity is opportunistic.

In past operations, Peach Sandstorm relied heavily, but not exclusively, on password spray attacks as a means of gaining access to targets of interest. In some cases, Peach Sandstorm has used this tradecraft to compromise an intermediate target and enable access to downstream environments. As one example, Peach Sandstorm carried out a wave of attacks in 2019 that coincided with a rise in tensions between the United States and the Islamic Republic of Iran.

Unlike password spray operations which are noisy by definition, a subset of Peach Sandstorm’s 2023 post-compromise activity has been stealthy and sophisticated. Many of the cloud-based tactics, techniques, and procedures (TTPs) seen in these most recent campaigns are materially more sophisticated than capabilities used by Peach Sandstorm in the past.

Intrusion chain

Microsoft observed Peach Sandstorm using two distinct sets of TTPs in the early stages of the intrusion lifecycle in 2023 attacks. In later stages of known compromises, the threat actor used different combinations from a set of known TTPs to drop additional tools, move laterally, and ultimately exfiltrate data from a target.

Path 1: Password spray activity, internal reconnaissance with AzureHound or Roadtools, and multiple persistence mechanisms

Password spray activity

Between February and July 2023, Peach Sandstorm carried out a wave of password spray attacks attempting to authenticate to thousands of environments. Password spraying is a technique where threat actors attempt to authenticate to many different accounts using a single password or a list of commonly-used passwords. Unlike brute force attacks that target a single account using many passwords, password spray attacks help adversaries maximize their chances for success and minimize the likelihood of automatic account lockouts.

Even a single compromised account could allow an adversary to conduct reconnaissance, move laterally, or access sensitive resources, often without attracting attention from defenders.

Long-running password spray campaigns offer insight into adversaries’ pattern of life. Activity observed in this campaign aligned with an Iranian pattern of life, particularly in late May and June, where activity occurred almost exclusively between 9:00 AM and 5:00 PM Iran Standard Time (IRST). While Peach Sandstorm has carried out high-volume password spray campaigns in the past, elements of the most recent campaign were unique. Specifically, Peach Sandstorm consistently conducted the password sprays from TOR IPs and used a “go-http-client” user agent.

Internal reconnaissance with AzureHound or Roadtools

In a small subset of instances where Peach Sandstorm successfully authenticated to an account in a targeted environment, Microsoft observed the threat actor using AzureHound or Roadtools to conduct reconnaissance in Microsoft Entra ID (formerly Azure Active Directory). In this campaign, Peach Sandstorm used AzureHound, a Go binary that collects data from Microsoft Entra ID and Azure Resource Manager through the Microsoft Graph and Azure REST APIs, as a means of gathering information on a system of interest. Similarly, Roadtools, a framework to access Microsoft Entra ID, allowed Peach Sandstorm to access data in a target’s cloud environment and conveniently dump data of interest to a single database.

AzureHound and Roadtools have functionality that is used by defenders, red teams, and adversaries. The same features that make these tools useful to legitimate users, like pre-built capabilities to explore and seamlessly dump data in a single database, also make these tools attractive options for adversaries seeking information about or from a target’s environment.

Multiple persistence mechanisms

In cases where Microsoft observed this particular intrusion chain, the threat actor used one or more persistence mechanisms. In some cases, Peach Sandstorm created a new Azure subscription on a target’s tenant and/or leveraged previously compromised Azure resources. These subscriptions were subsequently used to facilitate communication with Peach Sandstorm’s infrastructure.

Peach Sandstorm also abused Azure Arc, a capability that allows users to secure, develop, and operate infrastructure, applications, and Azure services anywhere, to persist in compromised environments. In this campaign, Peach Sandstorm installed the Azure Arc client on a device in the compromised environment and connected it to an Azure subscription controlled by Peach Sandstorm. This effectively allowed Peach Sandstorm to control devices in a target’s on-premises environment from Peach Sandstorm’s cloud.

Path 2: Remote exploitation of vulnerable internet-facing applications

Initial access using remote exploitation

In this wave of activity, Peach Sandstorm also attempted to exploit vulnerabilities with a public proof-of-concept (POC) in Zoho ManageEngine or Confluence, to access targets’ environments.

• CVE-2022-47966 is a remote code execution vulnerability affecting a subset of on-premises Zoho ManageEngine products. Microsoft recommends organizations using vulnerable applications patch this vulnerability as multiple groups have been observed exploiting this vulnerability.
• CVE-2022-26134 is a remote code execution vulnerability in Confluence Server and Data Center. Recommendations that help organizations protect against exploitation of multiple vulnerabilities, including CVE-2022-26134, can be found in the recommendations section of this report.

Post-compromise activity

The following post-compromise activity affected organizations in the defense, satellite, and pharmaceutical sectors:

• In a subset of intrusions in this campaign, Peach Sandstorm deployed AnyDesk, a commercial remote monitoring and management tool (RMM) to maintain access to a target. AnyDesk has a range of capabilities that allow users to remotely access a network, persist in a compromised environment, and enable command and control (C2). The convenience and utility of a tool like AnyDesk is amplified by the fact that it might be permitted by application controls in environments where it is used legitimately by IT support personnel or system administrators.

• In a March 2023 intrusion, Peach Sandstorm conducted a Golden SAML attack to access a target’s cloud resources. In a Golden SAML attack, an adversary steals private keys from a target’s on-premises Active Directory Federated Services (AD FS) server and use the stolen keys to mint a SAML token trusted by a target’s Microsoft 365 environment. If successful, a threat actor could bypass AD FS authentication and access federated services as any user.

• In at least one intrusion, Microsoft observed Peach Sandstorm using a legitimate VMWare executable to carry out a search order hijack. DLL search order hijacking allows adversaries to introduce malicious code into an environment in a way that blends in with normal activity.

• In a handful of environments, Microsoft observed Peach Sandstorm using EagleRelay to tunnel traffic back to their infrastructure. In these instances, Peach Sandstorm created a new virtual machine in a compromised Azure subscription. These virtual machines were used to run EagleRelay, a custom tool, to tunnel traffic between actor-controlled systems and targets’ systems. In at least one case, Microsoft also saw Peach Sandstorm attempting to move laterally in a compromised environment using remote desktop protocol (RDP).

Additional context

The capabilities observed in this campaign are concerning as Microsoft saw Peach Sandstorm use legitimate credentials (gleaned from password spray attacks) to authenticate to targets’ systems, persist in targets’ environments, and deploy a range of tools to carry out additional activity. Peach Sandstorm also created new Azure subscriptions and leveraged the access these subscriptions provided to conduct additional attacks in other organizations’ environments. While the specific effects in this campaign vary based on the threat actor’s decisions, even initial access could adversely impact the confidentiality of a given environment. Microsoft continues to work across its platforms to identify abuse, take down malicious activity, and implement new proactive protections to discourage malicious actors from using our services. We encourage customers and the industry to report abuse.

As Peach Sandstorm increasingly develops and uses new capabilities, organizations must develop corresponding defenses to harden their attack surfaces and raise costs for these attacks. Microsoft will continue to monitor Peach Sandstorm activity and implement robust protections for our customers.

Mitigations

To harden an attack surface against Peach Sandstorm activity, defenders can implement the following:

• Reset account passwords for any accounts targeted during a password spray attack. If a targeted account had system-level permissions, further investigation may be warranted.
• Revoke session cookies in addition to resetting passwords
  • Revoke any multifactor authentication (MFA) setting changes made by the attacker on any compromised users’ accounts
  • Require re-challenging MFA for MFA updates as the default

• Implement the Azure Security Benchmark and general best practices for securing identity infrastructure, including:
  • Create conditional access policies to allow or disallow access to the environment based on defined criteria.
  • Block legacy authentication with Microsoft Entra ID by using Conditional Access. Legacy authentication protocols don’t have the ability to enforce MFA, so blocking such authentication methods will prevent password spray attackers from taking advantage of the lack of MFA on those protocols.
  • Enable AD FS web application proxy extranet lockout to protect users from potential password brute force compromise.
• Secure accounts with credential hygiene:
  • Practice the principle of least privilege and audit privileged account activity in your Microsoft Entra ID environments to slow and stop attackers.
  • Deploy Microsoft Entra ID Connect Health for Active Directory Federation Services (AD FS). This captures failed attempts as well as IP addresses recorded in AD FS logs for bad requests in the Risky IP report.
  • Use Microsoft Entra ID password protection to detect and block known weak passwords and their variants.
  • Turn on identity protection in Microsoft Entra ID to monitor for identity-based risks and create policies for risky sign ins.
• Use MFA to mitigate successful password spray attacks. Keep MFA always-on for privileged accounts and apply risk-based MFA for normal accounts.
• Consider transitioning to a passwordless primary authentication method, such as Azure MFA, certificates, or Windows Hello for Business.
• Secure RDP or Windows Virtual Desktop endpoints with MFA to harden against password spray or brute force attacks.

Securing critical assets like AD FS servers is a high-value measure to protect against golden SAML attacks. The guidance provided below is applicable beyond just Peach Sandstorm activity and can help organizations harden their attack surfaces against a range of threats.

• It’s critical to treat your AD FS servers as a Tier 0 asset, protecting them with the same protections you would apply to a domain controller or other critical security infrastructure. AD FS servers provide authentication to configured relying parties, so an attacker who gains administrative access to an AD FS server can achieve total control of authentication to configured relying parties (include Microsoft Entra ID tenants configured to use the AD FS server).
• Practicing credential hygiene, notably the recommendations provided above, is critical for protecting and preventing the exposure of highly privileged administrator accounts. This especially applies on more easily compromised systems like workstations with controls like logon restrictions and preventing lateral movement to these systems with controls like the Windows Firewall.
• Migration to Microsoft Entra ID (formerly Azure Active Directory) authentication is recommended to reduce the risk of on-premises compromises moving laterally to your authentication servers. Customers can use the following references on migration:
  • Use the activity report to move AD FS apps to Microsoft Entra ID
  • Move application authentication to Microsoft Entra ID

Indicators of compromise

Detection details

Microsoft Defender for Endpoint

Alerts with the following titles in the security center can indicate Peach Sandstorm activity on your network:

• Peach Sandstorm actor activity detected

Microsoft Defender for Identity

The following alerts might indicate activity associated with password spray campaigns.

• Password Spray
• Atypical travel
• Unfamiliar Sign-in properties

Microsoft Defender for Cloud Apps

The following alerts might indicate activity associated with password spray campaigns.

• Activity from a Tor IP address
• Suspicious Administrative Activity
• Impossible travel activity
• Multiple failed login attempts
• Activity from a password-spray associated IP address

Organizations with Defender for Cloud Apps can turn on app governance, a set of security and policy management capabilities designed for OAuth-enabled apps registered on Azure Active Directory, Google, and Salesforce. The following detections in App governance might indicate activity associated with password spray campaigns.

• Numerous Azure AD enumeration calls using PowerShell
• Suspicious enumeration activities performed using AAD PowerShell

Hunting queries

Microsoft Sentinel

Microsoft customers can use a range of Microsoft Sentinel content to help detect Peach Sandstorm activity described in this blog. The Azure Active Directory solution contains several analytics rules and hunting queries for Microsoft Entra ID data that can help uncover initial access activity including password sprays. Specific analytics rules of value include:

• Password spray attack against Microsoft Entra ID application
• Potential Password Spray Attack (Uses Authentication Normalization)
• Okta – Potential Password Spray Attack

References

• https://www.cyberwarcon.com/apt33
• https://bloodhound.readthedocs.io/en/latest/data-collection/azurehound.html
• https://github.com/dirkjanm/ROADtools
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=2022-47966
• https://www.manageengine.com/security/advisory/CVE/cve-2022-47966.html
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-26134
• https://confluence.atlassian.com/doc/confluence-security-advisory-2022-06-02-1130377146.html

Further reading

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog: https://aka.ms/threatintelblog.

To get notified about new publications and to join discussions on social media, follow us on Twitter at https://twitter.com/MsftSecIntel.

The post Peach Sandstorm password spray campaigns enable intelligence collection at high-value targets appeared first on Microsoft Security Blog.