Third Party SSH Access Using Vendor Key

Darshan Thummar@Mighty

•updated Jun 11, 2026•0•0•4

This rule detects SSH connections to the internal network ($HOME_NET) on port 22. It specifically looks for the 'SSH-2.0' content in the TCP flow to the server. A threshold is set to trigger an alert if three such connections are observed from the same source within 60 seconds. The rule's message suggests it's intended to identify third-party SSH access potentially using a vendor key, implying an attempt to detect unauthorized or unusual SSH activity.