Suspicious Windows Defender Exclusion Added via Add-MpPreference

ATT&CK techniques

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects use of Add-MpPreference to add Windows Defender path or extension exclusions, a defense-evasion step observed in the intrusion where the actor carved out exclusions before staging malware. Excluding a directory or file type from scanning lets subsequent payloads run undetected. While admins occasionally set exclusions, unexpected additions on endpoints frequently precede malware deployment.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Suspicious Windows Defender Exclusion Added via Add-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.

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