Suspicious Certutil Encode or Decode for Payload Obfuscation (via process_creation)

ATT&CK techniques

Defense Evasion

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

What it detects

This rule detects certutil being used with the -encode or -decode options to transform files between binary and Base64 form. Threat actors exploiting Citrix NetScaler CVE-2023-4966 used certutil to stage and deobfuscate tooling while evading content inspection. This living-off-the-land use of certutil for data encoding is a common defense-evasion and deobfuscation behavior.

Reporting behind it

Related detections9 linkedT1140 — drag to rearrange

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Suspicious Certutil Encode or Decode for Payload Obfuscation (via process_creation)

Pivot detection · T1140 · 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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