Suspicious SD-WAN Compromise Reverse Tunnel via gsocket

PremiumReviewedSigma · Medium · v1
Product
linux
Category
process_creation
Author
HuntRule
Published
2026-05-20
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 execution of the gsocket or gs-netcat tunneling utilities, matching the Cisco Catalyst SD-WAN exploitation where operators deploy gsocket to establish an outbound relay through firewalls. The Global Socket toolkit provides resilient encrypted access that bypasses inbound restrictions on compromised network devices. Presence of these tools on an appliance indicates covert remote access.

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Suspicious SD-WAN Compromise Reverse Tunnel via gsocket
Pivot detection · T1090 · 9 related

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