T1685 GPO or Entra Security Downgrade (Excludes Routine/Read-Only Changes)

Arnold Chan@slaz

•updated Sep 8, 2026•0•0•1

This rule detects modifications to Group Policy Objects (GPO) or Microsoft Entra (formerly Azure AD) policies that weaken established security controls. For GPO, it monitors Event ID 5136 for changes to security-relevant attributes (e.g., disabling firewall or real-time monitoring) in Active Directory. For Entra, it monitors audit logs for administrative operations that reduce security posture, such as disabling MFA, lowering authentication trust, or deleting Conditional Access policies. It includes filters to exclude legitimate, documented change management activities.