Smoothwall Express 3.1 'outgoing.cgi' Cross-Site Scripting

Smoothwall Express 3.1-SP4-polar-x86_64-update9 contains a reflected cross-site scripting vulnerability that allows attackers to inject malicious scripts by manipulating the MACHINE and MACHINECOMMENT parameters. Attackers can send POST requests to the outgoing.cgi endpoint with script payloads to execute arbitrary JavaScript in users' browsers and steal session data.