huntrule

Windows Indirect Command Execution via Program Compatibility Assistant pcwrun.exe

Alerts on child processes spawned by pcwrun.exe, indicating indirect command execution via Program Compatibility Assistant.

FreeReviewedSigma · Low · v2
Product
windows
Category
process_creation
Author
A. Sungurov , oscd.community (SigmaHQ), DRL 1.1
Published
2020-10-12
Updated
2026-07-31
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 identifies process launches where the parent process is the Program Compatibility Assistant executable (pcwrun.exe). Attackers can abuse this legitimate Windows component to run commands indirectly while blending into normal execution paths. It relies on process creation telemetry, specifically the parent image path ending with \pcwrun.exe.

Reporting behind it

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Windows Indirect Command Execution via Program Compatibility Assistant pcwrun.exe
Pivot detection · T1218 · 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.