huntrule

Windows OpenWith.exe Launches Another Binary via /c

Flags Windows OpenWith.exe executions that include '/c', indicating it launched another binary.

FreeReviewedSigma · High · v2
Product
windows
Category
process_creation
Author
Beyu Denis, oscd.community (rule), @harr0ey (idea) (SigmaHQ), DRL 1.1
Published
2019-10-12
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 creation where an executable named OpenWith.exe is launched with a command line containing the '/c' parameter. Attackers can use this behavior to indirectly start another binary while blending into legitimate Windows functionality. The detection relies on Windows process creation telemetry, matching the process image ending with '\OpenWith.exe' and the presence of '/c' in the command line.

Reporting behind it

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Suspicious Renamed git Binary gcmd.exe Execution (via process_creation)
Windows OpenWith.exe Launches Another Binary via /c
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.