huntrule

Windows: MSOHTMED.EXE Arbitrary File Download Using HTTP/FTP URLs

Alerts when MSOHTMED.EXE is executed with HTTP/FTP URLs to download an arbitrary file.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-08-19
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 process creation where MSOHTMED.EXE (identified by filename and OriginalFileName) is launched with a command line containing HTTP or FTP URLs. Attackers can use this behavior to retrieve arbitrary payloads or stage additional components while blending into normal Windows execution patterns. The detection relies on Windows process creation telemetry including Image path, OriginalFileName, and CommandLine content.

Reporting behind it

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Windows: MSOHTMED.EXE Arbitrary File Download Using HTTP/FTP URLs
Pivot detection · T1218 · 9 related

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