Suspicious Remote File Download via certutil URLCache (via process_creation)

ATT&CK techniques

Defense Evasion → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1140Deobfuscate/Decode Files or Information
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects certutil.exe downloading a file from a remote URL using the urlcache and split flags. Rapid7 observed this living-off-the-land download technique in an exposed WebDAV malware delivery lab used to pull additional tooling onto compromised hosts. certutil is a certificate utility and its use as a file downloader is a well-known ingress and defense evasion technique.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange

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Suspicious Remote File Download via certutil URLCache (via process_creation)

Pivot detection · T1105 · 9 related

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

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