Suspicious File Download via Certutil URLCache

ATT&CK techniques

Execution → C2

Recon
Resource Dev
Initial Access
Execution
- T1197BITS Jobs
Persistence
- T1197BITS Jobs
Priv Esc
Defense Evasion
- T1197BITS Jobs
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects certutil being used with its url cache download flags which the ALPHV intrusion leveraged as a living off the land downloader to stage tooling and this matters because certutil is a signed system binary frequently abused to retrieve remote payloads and its download flags rarely appear in legitimate certificate operations.

Reporting behind it

Related detections9 linkedT1105 — drag to rearrange

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Windows BITSAdmin File Download via bitsadmin.exe with Transfer/Addfile Arguments

Suspicious Remote HTA Payload Execution via MSHTA

Possible PurpleFox MSHTA to Msiexec Remote MSI Chain

Suspicious File Download via Certutil URLCache

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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