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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
Suspicious Vulnerable Intel Ethernet Driver Load for BYOVD via SCATTERED SPIDER (via driver_load)
Malicious Defender Disable And Executable Exclusion Via Registry
Malicious UAC Disable via EnableLUA Registry Modification (via registry_set)
Malicious AMSI and ETW Patching via PowerShell Script
Malicious PowMix AMSI Bypass via amsiInitFailed
Suspicious ThrottleStop Driver Abuse for Defense Evasion in Ransomware Attacks
Malicious Disabling of Microsoft Defender Real-Time Protection via SystemSettingsAdminFlows by DeadLock Ransomware
Suspicious Security Software Uninstallation via WMIC Product Call Uninstall (Chaos Ransomware)
Suspicious Security Product Uninstall via wmic product call uninstall
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.