huntrule

Windows: Process creation event for Sysmon uninstall using Sysmon -u

Flags attempts to uninstall Sysmon on Windows by running Sysmon with the -u flag.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
frack113 (SigmaHQ), DRL 1.1
Published
2022-01-12
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

  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 identifies process executions where Sysmon binaries (Sysmon64.exe, Sysmon64a.exe, or Sysmon.exe) are started with the uninstall flag (-u). Uninstalling Sysmon can reduce visibility into host activity and may be used as defense impairment. It relies on Windows process creation telemetry, including the process image name, its description, and the command line contents.

Reporting behind it

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Suspicious ThrottleStop Driver Abuse for Defense Evasion in Ransomware Attacks
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Suspicious Security Software Uninstallation via WMIC Product Call Uninstall (Chaos Ransomware)
Suspicious Security Product Uninstall via wmic product call uninstall
Windows: Process creation event for Sysmon uninstall using Sysmon -u
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.