Suspicious Certutil Download and Certificate Installation via Living-off-the-Land

ATT&CK techniques

Defense Evasion → C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1553.004Install Root Certificate
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects certutil.exe being used to download files or install root certificates, a living-off-the-land technique observed in the ToolShell espionage intrusion. Certutil is frequently abused to stage second-stage payloads and add attacker certificates.

Reporting behind it

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Suspicious Certutil Download and Certificate Installation via Living-off-the-Land

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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