Suspicious GPG Decryption of Downloaded Payload via GPG

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-09-17
Updated
2026-09-17

ATT&CK techniques

Defense Evasion
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. 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.

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Suspicious GPG Decryption of Downloaded Payload via GPG
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Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.