Suspicious File Download via Certutil URLCache [Huntress] #2

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 downloading a remote file using the urlcache option, a LOLBIN download technique Huntress observed after Wing FTP CVE-2025-47812 exploitation. Attackers use certutil to retrieve payloads over HTTP while blending in with a trusted signed binary. Certutil retrieving content from a URL is a common ingress tool transfer indicator that warrants review of the fetched resource.

Reporting behind it

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Suspicious File Download via Certutil URLCache [Huntress] #2

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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