6.5Medium
CVE-2026-85693
Chatbot UI contains an authorization bypass vulnerability in the retrieval endpoint that allows authenticated attackers to access private file content belonging to other users by supplying arbitrary file UUIDs. The endpoint uses a service-role Supabase client that bypasses row-level security and fails to validate file ownership, enabling attackers to retrieve indexed content chunks from victim files through crafted POST requests.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 16% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 6.5 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N- CVSS v4
- 7.1
- Weakness
- CWE-639
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-04
- Last modified
- 2026-09-14
- Sources
- NVD
References
- https://github.com/mckaywrigley/chatbot-ui
- https://github.com/mckaywrigley/chatbot-ui/blob/81328b61d2a4ab597a7a057be70e785cf756d9f8/app/api/retrieval/retrieve/route.ts
- https://github.com/mckaywrigley/chatbot-ui/issues/2028
- https://www.vulncheck.com/advisories/chatbot-ui-cross-user-private-file-content-disclosure-via-retrieval-api