Malicious Defender Exclusion Addition 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 Add-MpPreference adding Microsoft Defender path or extension exclusions, carving out blind spots where malware can run and write files unscanned. This was observed during Cephalus ransomware deployment. Attacker-created exclusions let the encryptor and staging artifacts evade real-time protection.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Malicious Defender Exclusion Addition 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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