CVE-2026-87014: Open WebUI: Admin demoted through SSO role sync keeps read and write access to all users' notes

A user who is demoted from admin by an identity provider keeps admin-level read and write access to every user’s notes, over any Socket.IO connection that was already open when the demotion happened. Open WebUI caches the user’s role on the socket at connection time, and the two SSO role-sync paths, the reverse-proxy trusted role header and OAuth role mapping, changed the role in the database without tearing that cached session down. Only the admin user-management endpoints invalidated sessions, so a demotion driven by the identity provider left the old privileges live on the socket.