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

Windows Defender Tampering via Set-MpPreference and Exclusions

Suspicious Windows Defender Real-Time Protection Disabled via Policy Registry by Cephalus Ransomware

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Malicious Windows Defender Tampering via Set-MpPreference (via process_creation)

Malicious Container Runtime Tampering via chmod on runc (via process_creation)

In-Memory AMSI or ETW Bypass in PowerShell (via process_creation)

Malicious Microsoft Defender Critical Security Components Disabled - Command (via process_creation)

Malicious Microsoft Defender Service Deactivation Attempt - Command (via process_creation)

Malicious Wdigest Authentication Enabled - Reg via Command (via process_creation)

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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