GHSA-q855-8rh5-jfgq: ha-mcp: Add-on settings and policy routes are reachable without authentication at the bare root path

Summary In add-on mode, the ha-mcp settings UI routes are mounted both under the MCP secret path and at the bare root of the published port (:9583), so Home Assistant ingress can serve the "Open Web UI" button. The root-mounted routes perform no authentication — no secret, no Origin check, no CSRF token — so any client that can reach :9583 without the MCP secret can invoke them. Affected configurations Home Assistant add-on installations (host_network: true with port 9583 published), v7.6.0 and earlier. Docker and standalone installs are not affected — there the settings routes are mounted only under the secret path. Root-mounted routes in affected versions: tool visibility (/api/settings/tools GET/POST), feature flags (/api/settings/features GET/POST), the auto-backup suite (/api/settings/backups… incl. restore/delete, and /api/settings/backup-config), add-on restart (/api/settings/restart), and — when the opt-in Tool Security Policies feature is enabled — the approval-policy API (/api/policy/config GET/PUT, /api/policy/approve, /api/policy/deny, …). Impact Without authentication, a caller that reaches :9583 — a peer on the local network, a reverse proxy/tunnel that forwards the bare root path (e.g. a whole-host Cloudflared config), or a CSRF POST from a page open in a LAN browser — can read or change which MCP tools are exposed, toggle feature flags, list/view/restore/delete backups, restart the add-on, and (with Tool Security Policies enabled) read and rewrite the approval policy, disabling the human-approval gate on gated tools. There is no access to Home Assistant data, entities, or credentials, and no code execution. All effects are confined to the add-on's own configuration and lifecycle and are recoverable. The primary (same-LAN) vector is within the add-on's documented trusted-network model; remote reachability requires the operator to have reverse-proxied the bare port. Proof of concept With the add-on running and reachable on :9583, from any host