Potentially Suspicious WDAC Policy File Creation (via file_event)

This rule detects anomalous Windows Defender Application Control (WDAC) policy file creation from abnormal processes that could be misused by adversary to block EDR/AV components while allowing their own hostile code to run on the system.

SigmamediumWindowsv1
sigma
title: Potentially Suspicious WDAC Policy File Creation (via file_event)
id: 6d2467c2-0670-5e5d-979a-01668d90fba2
status: stable
description: This rule detects anomalous Windows Defender Application Control (WDAC) policy file creation from abnormal processes that could be misused by adversary to block EDR/AV components while allowing their own hostile code to run on the system.
references:
    - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/app-control-for-business/deployment/deploy-appcontrol-policies-using-group-policy
    - https://beierle.win/2024-12-20-Weaponizing-WDAC-Killing-the-Dreams-of-EDR/
    - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/app-control-for-business/deployment/appcontrol-deployment-guide
    - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/app-control-for-business/deployment/deploy-appcontrol-policies-with-script
    - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/app-control-for-business/deployment/deploy-appcontrol-policies-with-memcm
author: Huntrule Team
date: 2026-04-18
tags:
    - attack.defense-impairment
    - attack.defense-evasion
    - attack.t1562.001
logsource:
    category: file_event
    product: windows
detection:
    selection_target:
        TargetFilename|contains: '\Windows\System32\CodeIntegrity\'
    filter_main_images:
        Image|endswith:
            - '\Microsoft.ConfigurationManagement.exe'
            - '\WDAC Wizard.exe'
            - 'C:\Program Files\PowerShell\7-preview\pwsh.exe'
            - 'C:\Program Files\PowerShell\7\pwsh.exe'
            - 'C:\Windows\System32\dllhost.exe'
            - 'C:\Windows\System32\WindowsPowerShell\v1.0\powershell_ise.exe'
            - 'C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe'
            - 'C:\Windows\SysWOW64\dllhost.exe'
            - 'C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell_ise.exe'
            - 'C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe'
    filter_main_cli:
        - CommandLine|contains|all:
              - 'ConvertFrom-CIPolicy -XmlFilePath'
              - '-BinaryFilePath '
        - CommandLine|contains: 'CiTool --update-policy'
        - CommandLine|contains|all:
              - 'Copy-Item -Path'
              - '-Destination'
    filter_main_system:
        Image: 'System'
    filter_main_wuauclt:
        Image: 'C:\Windows\System32\wuauclt.exe'
    filter_main_wuaucltcore:
        Image:
            - 'C:\Windows\UUS\arm64\wuaucltcore.exe'
            - 'C:\Windows\UUS\Packages\Preview\arm64\wuaucltcore.exe'
    condition: selection_target and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.