Suspicious Plink SSH Tunnel Execution (via process_creation)

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

ATT&CK techniques

Lateral Movement
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects the Plink command line SSH client being launched with port forwarding flags, a tunneling technique used by the Agrius group to proxy traffic and reach internal systems. Adversaries abuse Plink to create covert channels through perimeter defenses, which is rarely benign on endpoints.

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Suspicious Denied RDP Login with Valid Credentials (via security)
Malicious RDP Session Hijacking via tscon Command Line
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Suspicious Plink SSH Tunnel Execution (via process_creation)
Pivot detection · T1021.001 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.