Suspicious Termination of Windows Security Health UI via taskkill

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 forced termination of SecHealthUI.exe, the Windows Security notification UI, via taskkill, an action GachiLoader takes to suppress security alerts to the user. Killing the Defender interface component is a defense-evasion behavior with little legitimate cause.

Reporting behind it

Related detections9 linkedT1685 — drag to rearrange

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Windows Defender Tampering via Set-MpPreference and Exclusions

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Suspicious Microsoft Defender Path Exclusion of User Directories (via process_creation)

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

Suspicious Termination of Windows Security Health UI via taskkill

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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