{"id":121754,"date":"2022-09-14T09:00:00","date_gmt":"2022-09-14T16:00:00","guid":{"rendered":"https:\/\/www.microsoft.com\/en-us\/security\/blog\/?p=121754"},"modified":"2023-06-19T10:34:34","modified_gmt":"2023-06-19T17:34:34","slug":"implementing-a-zero-trust-strategy-after-compromise-recovery","status":"publish","type":"post","link":"https:\/\/www.microsoft.com\/en-us\/security\/blog\/2022\/09\/14\/implementing-a-zero-trust-strategy-after-compromise-recovery\/","title":{"rendered":"Implementing a Zero Trust strategy after compromise recovery"},"content":{"rendered":"\n
After a successful compromise recovery effort, you are back in control. Likely, you gave your team a round of applause and took a sigh of relief. <\/p>\n\n\n\n
Now what? Is everything going back to as it was in the past? Absolutely not! A compromise recovery engagement is an accelerated way of doing numerous amounts of cybersecurity configuration and upgrades in a short amount of time. Just because the Domain Admins have basic protection it doesn’t mean that the full environment is secure yet.<\/p>\n\n\n\n
After a compromise recovery engagement, Microsoft\u2019s compromise recovery team follows up with what we call security strategic recovery. This is the plan for moving forward to get the environment up to date with security posture. The plan consists of different components like Securing Privileged Access and extended detection and response (XDR), depending on the organizational needs, but it all points in the same direction: moving ahead with Zero Trust<\/a> strategy over traditional network-based security.<\/p>\n\n\n\n After we have secured the most critical privileged servers (including Domain Controllers, called also \u201cTier 0\u201d server for on-premises environment) and privileged accounts (Domain Admins), the next step is to mitigate unauthorized privilege escalation for the Data\/Workload and Management plane (called also \u201cTier 1\u201d for on-premises environment).<\/p>\n\n\n\n An encryption attack that gets local admin permissions on all member servers will still be devastating, so a proper delegation model must be implemented. Ransomware can utilize this account to encrypt application and database servers in the same way as using a Domain Admin account. Different tools like PIM\/PAM and strategies can be used to strengthen the security of the Data\/Workload administrators and services. Please refer to the enterprise access model<\/a> for additional details.<\/p>\n\n\n\n During a compromise recovery, we are implementing what we call a \u201cTactical\u201d Privileged Access Workstation. While functional for the purpose of providing a secure workstation with a \u201cclean keyboard\u201d to operate in a compromised environment, it is not meant to be long-lasting and engineered for broader enterprise deployment.<\/p>\n\n\n\n Implementing a proper Privileged Access Workstation together with a broader Privileged Access environment for all administrative tasks is necessary to reduce attack vectors and risk of re-compromise.<\/p>\n\n\n\n The Privileged Access Workstation configuration must include security controls and policies that restrict local administrative access and productivity tools to minimize the attack surface to only what is absolutely required for performing sensitive job tasks. Please refer to Why are privileged access devices important<\/a> for additional details.<\/p>\n\n\n\n While performing compromise recovery, we implement \u201ctactical monitoring\u201d to supplement the customer’s investigation, leveraging a targeted implementation of Microsoft Defender suite<\/a> and Microsoft Sentinel<\/a> on all critical systems.<\/p>\n\n\n\n This is key to obtain visibility on the environment and respond quickly and efficiently to abnormal or suspicious activities before it turns into another security incident.<\/p>\n\n\n\n As part of a strategic security roadmap, we strongly recommend completing the implementation of XDR with Microsoft Defender Threat Protection<\/a> and leveraging automated investigation and remediation capabilities to save security operations teams’ time and effort.<\/p>\n\n\n\n Additional help to our customers to defend and manage their environment is now available from Microsoft through Microsoft Security Experts<\/a>.<\/p>\n\n\n\n The Strategic Recovery recommendation listed previously on using least privileged access for privileged administration and XDR for improving defenses are just initial steps into a broader Zero Trust journey (see Figure 1).<\/p>\n\n\n\nPrivileged administration<\/h2>\n\n\n\n
Privileged Access Workstation<\/h2>\n\n\n\n
From tactical monitoring to XDR<\/h2>\n\n\n\n
Zero Trust journey<\/h2>\n\n\n\n