huntrule

Windows Proxy Execution via wuauclt.exe (UpdateDeploymentProvider/RunHandlerComServer)

Alerts when wuauclt.exe is executed with UpdateDeploymentProvider/RunHandlerComServer-related parameters indicative of proxy execution.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
Roberto Rodriguez (Cyb3rWard0g), OTR (Open Threat Research), Florian Roth (Nextron Systems), Sreeman, FPT.EagleEye Team (SigmaHQ), DRL 1.1
Published
2020-10-12
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 flags process creation where the Windows Update Client binary wuauclt.exe is launched with command-line parameters associated with UpdateDeploymentProvider and RunHandlerComServer. Attackers may abuse this legitimate Windows component to proxy or stage execution while blending in with expected update-related activity. The detection relies on Windows process creation telemetry, matching the image/OriginalFileName for wuauclt.exe and specific command-line substrings while excluding several known benign update deployment patterns.

Reporting behind it

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Malicious ClickFix Execution Chain Spawning MSHTA via Pcalua on EtherRAT Infection
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Windows Proxy Execution via wuauclt.exe (UpdateDeploymentProvider/RunHandlerComServer)
Pivot detection · T1218 · 9 related

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