Suspicious Outbound Connection to InvisibleFerret C2 Ports 1224 and 1245

PremiumReviewedSigma · Low · v1
Category
network_connection
Author
HuntRule
Published
2026-08-15
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 outbound TCP connections to the uncommon ports 1224 and 1245 used by the InvisibleFerret and BeaverTail command and control servers in the North Korean job-hunter campaigns per Unit 42. These fixed high ports carry the actor heartbeat and tasking traffic which is rare for legitimate applications and flags an infected host.

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Suspicious Outbound Connection to InvisibleFerret C2 Ports 1224 and 1245
Pivot detection · T1071.001 · 9 related

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