Malicious Windows Defender Disable via Policy Registry Keys

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 modification of the Windows Defender policy registry values that switch off antispyware antivirus and real time monitoring as performed in the SystemBC intrusion described by WithSecure. Disabling Defender through policy keys is a defense evasion step attackers take to clear the path for credential theft and ransomware staging.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Suspicious Windows Defender Exclusion Enumeration via reg query (via process_creation)

Malicious Windows Defender Exclusion Added via PowerShell (via process_creation)

Malicious BYOVD EDR Kill via Renamed GMER Driver by Agonizing Serpens

Malicious Windows Defender Disable via Policy Registry Keys

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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