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Windows: rundll32.exe spawning explorer.exe child process (shell32.Control_RunDLL)

Alerts on rundll32.exe spawning explorer.exe, an uncommon child process pattern that may indicate stealthy execution via shell components.

FreeReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
elhoim, CD_ROM_ (SigmaHQ), DRL 1.1
Published
2022-04-27
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 executions where rundll32.exe spawns explorer.exe as a child process. Such a process tree is uncommon and can indicate attempts to launch a user-facing interface or mask execution through Windows shell components. It relies on process creation telemetry, matching on parent process image ending in rundll32.exe and child process image ending in explorer.exe, while excluding cases where the parent command line contains the specific shell32.dll Control_RunDLL string.

Reporting behind it

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Suspicious Persistence via pcalua Launching rundll32 Control_RunDLL
Suspicious Rundll32 Executing DLL Start Export With Control Flags
Suspicious Rundll32 Execution of Timestamp-Named DLL
Windows: rundll32.exe spawning explorer.exe child process (shell32.Control_RunDLL)
Pivot detection · T1218.011 · 9 related

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