Suspicious Certutil URLCache Download

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
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.

Reporting behind it

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Suspicious Certutil URLCache Download

Pivot detection · T1105 · 9 related

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