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Windows Security 4697: Obfuscated PowerShell via rundll32 shell32 shellexec_rundll

Alert on Security EID 4697 where service installation references rundll32/shell32.dll to launch PowerShell.

FreeReviewedSigma · Medium · v2
Product
windows
Service
security
Author
Timur Zinniatullin, oscd.community (SigmaHQ), DRL 1.1
Published
2020-10-18
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 System Security Extension events where service execution references rundll32 (rundll32.exe) with shell32.dll and the shellexec_rundll entry, and the command line contains the string powershell. Attackers may use rundll32 to launch PowerShell in a way that blends into legitimate system behavior and can hinder straightforward command-line analysis. It relies on Windows Security audit EventID 4697 telemetry, matching the recorded service file name content and required substrings.

Reporting behind it

Related detections9 linkedT1027 — drag to rearrange
Malicious FIN7 Powertrash Loader Execution via Obfuscated PowerShell (via process_creation)
Suspicious XOR Obfuscated PowerShell from ClickFix Distribution
Suspicious PowerShell Executing Code from Environment Variable (via process_creation)
Suspicious In-Memory Runspace Execution via PowerShell Script Block
Suspicious Encoded PowerShell Using Base64 Stream Decompression Routines (via process_creation)
Suspicious PowerShell In-Memory Execution with AES Decryption
Suspicious Encoded PowerShell Command Execution
Suspicious PEAKLIGHT Memory-Only PowerShell Downloader Flags (via process_creation)
Obfuscated PowerShell Script: Indirect Cmdlet Execution via ExportedCommands Array Index
Windows Security 4697: Obfuscated PowerShell via rundll32 shell32 shellexec_rundll
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.