CVE-2026-85693: Authorization Bypass Through User-Controlled Key in mckaywrigley chatbot-ui

The chatbot-ui product by mckaywrigley contains an authorization bypass vulnerability in its retrieval endpoint. This endpoint uses a service-role Supabase client that bypasses row-level security policies and fails to verify that the requesting user owns the file identified by the UUID. As a result, an authenticated attacker can supply arbitrary file UUIDs in POST requests to retrieve private content chunks from files belonging to other users. This flaw enables unauthorized access to sensitive data stored in the system.

An authenticated attacker can access private file content of other users without proper authorization. This compromises confidentiality of user data stored in the chatbot-ui system. The vulnerability does not require user interaction and has a low attack complexity, increasing the risk of unauthorized data disclosure.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict access to the affected retrieval endpoint to trusted users only and monitor for suspicious activity involving file UUIDs. Implement additional access control checks to validate file ownership before returning content. Avoid using service-role clients that bypass row-level security for user data retrieval.