Suspicious GPG Decryption of Downloaded Payload via GPG

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 batch mode GPG decryption on Windows endpoints which GHOSTPULSE uses to decrypt a downloaded tar gpg payload with a preset passphrase supplied on a file descriptor. Non-interactive gpg decrypt invocations are uncommon on typical workstations and here signal payload staging and defense evasion.

Reporting behind it

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Suspicious GPG Decryption of Downloaded Payload via GPG

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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