Malicious certutil Decodehex Payload Reconstruction by DarkGate

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1140Deobfuscate/Decode Files or Information
- T1218System Binary Proxy Execution
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects certutil being run with the decodehex option to reconstruct a binary from a downloaded hex-encoded file, a step DarkGate uses to rebuild an AutoHotkey interpreter from a dropped a.bin file. Abusing certutil for decoding is a living-off-the-land technique that evades signature-based download controls. Detecting this exposes payload deobfuscation during the DarkGate infection chain.

Reporting behind it

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Malicious certutil Decodehex Payload Reconstruction by DarkGate

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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