Malicious Certutil URL Cache Download of Remote Payload

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 being used with the urlcache and split flags to download a remote executable, a living-off-the-land technique used in the intrusion analyzed by Huntress to fetch agent.exe. Certutil is a certificate utility and its use to retrieve arbitrary files over HTTP is almost always malicious ingress tool transfer. Attackers rely on it to evade controls that block common download utilities.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange

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Malicious Certutil URL Cache Download of Remote Payload

Pivot detection · T1105 · 9 related

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