Web App Behind OPNsense: Expose & Exploit

A deliberately vulnerable PHP support portal runs on an internal host behind OPNsense, but the NAT port-forward that should expose it to the WAN is misconfigured. Repair the firewall to reach the portal from the attacker box, then exploit the app to capture the flag. A blend of network (NAT/firewall) and web exploitation — derived from the "Pivot through OPNsense" lab.