Malicious Windows Defender Root Exclusion via Add-MpPreference (via process_creation)

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-21
Updated
2026-09-21

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 detects the use of Add-MpPreference to register a broad exclusion path covering an entire drive root such as C. The D3F@ck Malware-as-a-Service loader uses this technique to disable Microsoft Defender scanning of its staging locations before dropping additional payloads. Blanket root exclusions are almost always malicious and blind the endpoint to all downstream tooling.

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Malicious Windows Defender Root Exclusion via Add-MpPreference (via process_creation)
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.