huntrule

Windows: File Download via CertOC.exe Using -GetCACAPS HTTP

Flags CertOC.exe launched with -GetCACAPS and an http URL, indicating a remote file retrieval attempt.

FreeReviewedSigma · Medium · v2
Product
windows
Category
process_creation
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-05-16
Updated
2026-07-31
AnalysisDetection

ATT&CK techniques

C2

  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

Identifies process executions of CertOC.exe where the command line includes -GetCACAPS and an HTTP URL, indicating an attempt to download file content. This matters because CertOC.exe can be abused to retrieve remote resources, which may support further malicious activity. The detection relies on Windows process creation telemetry, matching the executable name/path and key substrings in the command line.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange
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Suspicious Certutil Download and Certificate Installation via Living-off-the-Land
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Windows: File Download via CertOC.exe Using -GetCACAPS HTTP
Pivot detection · T1105 · 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.