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Windows Security 4697: Obfuscated command uses rundll32 with shell32.dll

Alerts on EventID 4697 service command lines containing rundll32 with shell32.dll/shellexec_rundll and obfuscation-like script fragments.

FreeReviewedSigma · High · v2
Product
windows
Service
security
Author
Nikita Nazarov, oscd.community (SigmaHQ), DRL 1.1
Published
2020-10-09
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

Execution → 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 Windows Security audit events (EventID 4697) where the registered service command line contains an obfuscation pattern along with rundll32 usage of shell32.dll and related rundll export strings. Attackers may use this execution path to hide their true intent while launching script-related commands. It relies on the Security log capturing the service installation details, specifically the ServiceFileName content.

Reporting behind it

Related detections9 linkedT1027 — drag to rearrange
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Malicious Emmenhtal JavaScript Loader Spawning Encoded PowerShell
Suspicious Python Interpreter Launching Encoded PowerShell via subprocess
Suspicious PS1Bot PowerShell Payload Written to ProgramData (via file_event)
Malicious Non-Interactive Encoded PowerShell Stager (via process_creation)
Suspicious Hidden PowerShell Executing Substring of Dropped File
PowerShell Encoded or Download-Cradle Command Line (via process_creation)
Obfuscated Encoded PowerShell Payload Deployed - PowerShell (via powershell)
Suspicious PowerShell AES Decryption and Reflective Method Invocation in SolarMarker
Windows Security 4697: Obfuscated command uses rundll32 with shell32.dll
Pivot detection · T1027 · 9 related

Changelog

v2
  1. v2
    Candidate ingested via manual entry.2026-07-31
  2. v1
    No changelog recorded for this version.2026-07-30

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