CVE-2026-73665 FreePBX UCP: Unauthenticated remote code execution via socket.io namespace auth bypass and AMI action injection

FreePBX is an open source IP PBX. Prior to 17.0.9, the UCP Node server on ports 8001 and 8003 uses io.usecheckAuth in node/lib/server.js, but Socket.IO version 4 applies that middleware only to the default namespace. An unauthenticated client can connect to custom namespaces that do not...