Suspicious OpenSSH Reverse Tunnel Establishment via ssh.exe

PremiumReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
HuntRule
Published
2026-08-21
Updated
2026-08-28

ATT&CK techniques

C2
  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. Exfiltration

  13. Impact

What it detects

This rule detects ssh.exe launched with the -R remote-forwarding switch to establish a reverse tunnel. In Talos IR ransomware engagements operators used OpenSSH reverse tunnels to proxy traffic back into the victim network for persistent access, so this is a protocol-tunneling indicator that should be correlated with the tunnel destination.

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Suspicious OpenSSH Reverse Tunnel Establishment via ssh.exe
Pivot detection · T1219 · 9 related

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