Socket Filter Backdoor via Raw Socket Access

Darshan Thummar@Mighty

•updated Jun 11, 2026•0•0•5

This rule detects attempts to establish a raw socket connection that is not TCP, UDP, or ICMP. This behavior can be indicative of a socket filter backdoor, where an attacker uses raw sockets to bypass standard network stack processing and potentially sniff or inject arbitrary network traffic. The rule specifically looks for outgoing connections from the home network to any destination where the IP protocol is not 6 (TCP), 17 (UDP), or 1 (ICMP).