{"id":"c443012c-7928-43bf-ac20-7eda5efe61ad","title":"Suspicious Uninstall of Windows Defender Feature via PowerShell","description":"Detects the use of PowerShell with Uninstall-WindowsFeature or Remove-WindowsFeature cmdlets to disable or remove the Windows Defender GUI feature, a common technique used by adversaries to evade defenses.\n","author":"yxinmiracle","status":"experimental","level":"high","date":"2025-08-22","modified":"","tags":["attack.defense-impairment","attack.t1685"],"technique_ids":["T1685"],"logsource":{"category":"process_creation","product":"windows"},"falsepositives":["Unknown"],"references":["https://learn.microsoft.com/en-us/powershell/module/microsoft.windows.servermanager.migration/uninstall-windowsfeature","https://thedfirreport.com/2023/04/03/malicious-iso-file-leads-to-domain-wide-ransomware"],"source_path":"rules/windows/process_creation/proc_creation_win_powershell_uninstall_defender_feature.yml","source_sha256":"16ab1d3888d5bc540e30412a97059ca9fd9c6bbb607bd2f87decb12b8488168a","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/process_creation/proc_creation_win_powershell_uninstall_defender_feature.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Suspicious Uninstall of Windows Defender Feature via PowerShell\nid: c443012c-7928-43bf-ac20-7eda5efe61ad\nstatus: experimental\ndescription: |\n    Detects the use of PowerShell with Uninstall-WindowsFeature or Remove-WindowsFeature cmdlets to disable or remove the Windows Defender GUI feature, a common technique used by adversaries to evade defenses.\nreferences:\n    - https://learn.microsoft.com/en-us/powershell/module/microsoft.windows.servermanager.migration/uninstall-windowsfeature\n    - https://thedfirreport.com/2023/04/03/malicious-iso-file-leads-to-domain-wide-ransomware\nauthor: yxinmiracle\ndate: 2025-08-22\ntags:\n    - attack.defense-impairment\n    - attack.t1685\nlogsource:\n    category: process_creation\n    product: windows\ndetection:\n    selection_img:\n        - Image|endswith:\n              - '\\powershell_ise.exe'\n              - '\\powershell.exe'\n              - '\\pwsh.exe'\n        - OriginalFileName:\n              - 'PowerShell_ISE.EXE'\n              - 'PowerShell.EXE'\n              - 'pwsh.dll'\n    selection_cli_uninstall:\n        CommandLine|contains:\n            - 'Uninstall-WindowsFeature'\n            - 'Remove-WindowsFeature' # Only supported in Windows Server 2008 R2 and Windows 2012 R2\n    selection_cli_defender_feature:\n        CommandLine|contains: 'Windows-Defender'\n    condition: all of selection_*\nfalsepositives:\n    - Unknown\nlevel: high\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1685","id":"T1685","name":"Disable or Modify Tools","page":"techniques/enterprise/T1685/"}],"data_path":"data/detection-rules/c443012c-7928-43bf-ac20-7eda5efe61ad.json","kind":"sigma"}