CVE-2026-35036: Ech0 has Unauthenticated Server-Side Request Forgery in Website Preview Feature

Ech0 implements link preview (editor fetches a page title) through GET /api/website/title. That is legitimate product behavior, but the implementation is unsafe: the route is unauthenticated, accepts a fully attacker-controlled URL, performs a server-side GET, reads the entire response body into memory (io.ReadAll). There is no host allowlist, no SSRF filter, and InsecureSkipVerify: true on the outbound client.

Attacker outcome : Anyone who can reach the instance can force the Ech0 server to open HTTP/HTTPS URLs of their choice as seen from the server’s network position (Docker bridge, VPC, localhost from the process view). Go’s default http.Client follows redirects (unless disabled). Redirect chains can move the server-side request from an allowed-looking host to an internal target; the code does not disable this in SendRequest.