When the opt-in Web Clipper server is enabled in Joplin Desktop, the server in `packages/lib/ClipperServer.ts` sends an `Access-Control-Allow-Origin: *` header. This allows arbitrary websites to call the 'POST /auth' and 'GET /auth/check' API endpoints because the pairing endpoints do not reject HTTP or HTTPS origins. Since the desktop confirmation dialog does not identify the requesting origin, a user who approves the prompt grants the attacking page a permanent API token. This token allows continuous read and write access to notes, folders, tags, resources, and master keys.