Suspicious Certutil URLCache Download

PremiumReviewedSigma · High · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-06-03
Updated
2026-08-28

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. Exfiltration

  13. Impact

What it detects

This rule detects certutil.exe used with the urlcache option to download a remote file. The DragonRank SEO-poisoning operators abused certutil urlcache to pull additional tooling onto compromised IIS servers. Certutil functioning as a downloader is a living-off-the-land ingress technique that evades controls expecting a browser or dedicated transfer tool.

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