SSRF URL Parser Differential Attack via Double-Slash or Authority Confusion

Ibrahim Saud@tektrix

•updated Jun 30, 2026•1•0•2

This rule monitors for process creations spawned by common web application servers (e.g., nginx, python, java, php) where the command line arguments contain indicators of a Server-Side Request Forgery (SSRF) attempt. Specifically, it looks for suspicious URL schemes (file:, gopher:, dict:, ftp:), potential authority confusion patterns (targeting cloud metadata IPs), and encoded directory traversal characters when paired with sensitive paths like 'etc' or 'proc'.