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Windows PowerShell: Disable Microsoft Defender Scanning via Set-MpPreference

Flags PowerShell commands that disable Microsoft Defender scanning/protection settings using Set-MpPreference, including encoded variants.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-03-03
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule identifies PowerShell process executions that use Set-MpPreference to disable Microsoft Defender scanning and related protections (e.g., archive scanning, real-time monitoring, IOAV, and behavior monitoring). Attackers may impair endpoint defenses to reduce detection and increase the likelihood of persistence or successful execution. It relies on Windows process creation telemetry capturing the PowerShell command line, including both plain-text parameters and Base64-encoded command content or modifiers.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange
Malicious Windows Defender Disablement via MpCmdRun RemoveDefinitions
Malicious Unsigned VIB Installation on ESXi Host via esxcli (via process_creation)
Suspicious In-Memory PowerShell Execution from Web Server via Automation Assembly (via image_load)
Malicious EDR Evasion Driver Load from AnyDesk Directory via k.sys (via image_load)
Malicious Zemana Vulnerable Driver Load for EDR Termination (via image_load)
Suspicious EDRKillShifter Vulnerable Driver Load from User Temp Directory (via image_load)
Malicious AuKill EDR Killer Kernel Driver Load via Process Explorer Driver (via image_load)
Malicious FIN7 AvNeutralizer EDR Killer Execution via Masqueraded Binary (via process_creation)
Suspicious Process Explorer Kernel Driver Dropped as PED.sys via File Creation (via file_event)
Windows PowerShell: Disable Microsoft Defender Scanning via Set-MpPreference
Pivot detection · T1685 · 9 related

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