huntrule

Windows Process Creation: taskmgr.exe launched in LOCAL_SYSTEM context

Flags taskmgr.exe process creation when initiated under a LOCAL_SYSTEM-equivalent user context string.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2018-03-18
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Defense Evasion

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule matches process creation events where an executable ending with \taskmgr.exe is launched by a security context containing the string "AUTHORI" or "AUTORI" (to cover multiple Windows language settings), indicating LOCAL_SYSTEM. Attackers may abuse signed system utilities like Task Manager to blend into normal administrative activity or to execute stealthy payloads. The detection relies on Windows process creation telemetry, including the process image path and the initiating user/security-context field.

Reporting behind it

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Windows Process Creation: taskmgr.exe launched in LOCAL_SYSTEM context
Pivot detection · T1036 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.