Suspicious Winlogon Userinit Hijack for Persistence

ATT&CK techniques

Persistence → Priv Esc

Recon
Resource Dev
Initial Access
Execution
Persistence
- T1547.004Winlogon Helper DLL
Priv Esc
- T1547.004Winlogon Helper DLL
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects modification of the Winlogon Userinit value to a path other than the legitimate system userinit.exe, a logon persistence technique used by the Team9 malware family. Chaining an attacker binary into the Userinit key causes it to execute automatically during every interactive logon.

Reporting behind it

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Suspicious Winlogon Userinit Hijack for Persistence

Pivot detection · T1547.004 · 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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