Query: write Sigma for Detects possible addition of shadow credentials to an active directory object.
Matching passage: Sigma rule: Detects possible addition of shadow credentials to an active directory object.. Logsource: windows / security. Rule: title: Possible Shadow Credentials Added id: f598ea0c-c25a-4f72-a219-50c44411c791 status: test description: Detects possible addition of shadow credentials to an active directory object. references: - https://www.elastic.co/guide/en/security/8.4/potential-shadow-credentials-added-to-ad-object.html - https://cyberstoph.org/posts/2022/03/detecting-shadow-credentials/ - https://twitter.com/SBousseaden/status/1581300963650187264? author: Nasreddine Bencherchali (Nextron Systems), Elastic (idea) date: 2022-10-17 tags: - attack.persistence - attack.credential-access - attack.defense-impairment - attack.t1556 logsource: product: windows service: security definition: The "Audit Directory Service Changes" logging policy must be configured in order to receive events. Audit events are generated only for objects with configured system access control lists (SACLs). Audit events are generated only for objects with configured system access control lists (SACLs) and only when accessed in a manner that matches their SACL settings. This policy covers the following events ids - 5136, 5137, 5138, 5139, 5141. Note that the default policy does not cover User objects. For that a custom AuditRule need to be setup (See https://github.com/OTRF/Set-AuditRule) detection: selection: EventID: 5136 AttributeLDAPDisplayName: msDS-KeyCredentialLink condition: selection falsepositives: - Modifications in the msDS-KeyCredentialLink attribute can be done legitimately by the Azure AD Connect synchronization account or the ADFS service account. These accounts can be added as Exceptions. (From elastic FP section) level: high
Near-miss passage: Sigma rule: Detects when AppLocker "Audit only" enforcement mode reports that an Application, DLL, Script, MSI, or Packaged-App woul. Logsource: windows / applocker. Rule: title: AppLocker Application Would Have Been Blocked id: 557e3bd3-7f21-495d-8d50-7c8bdfb8041c status: experimental description: 'Detects when AppLocker "Audit only" enforcement mode reports that an Application, DLL, Script, MSI, or Packaged-App would have been blocked if AppLocker "Enforce rules" enforcement mode was enabled. ' references: - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/windows-defender-application-control/applocker/what-is-applocker - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/windows-defender-application-control/applocker/using-event-viewer-with-applocker - https://www.splunk.com/en_us/blog/security/deploy-test-monitor-mastering-microsoft-applocker-part-2.html - https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/ee844150(v=ws.11) author: heyyanu date: 2026-03-26 tags: - attack.execution - attack.t1204.002 - attack.t1059.001 - attack.t1059.003 - attack.t1059.005 - attack.t1059.006 - attack.t1059.007 logsource: product: windows service: applocker detection: selection: EventID: - 8003 - 8006 - 8021 - 8024 condition: selection falsepositives: - Expected during AppLocker policy testing and audit mode deployments level: medium