Auth bypass in Mckaywrigley Chatbot-Ui
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.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (36.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 36th percentile — 36.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.002
Affected products
Weakness classification (CWE)
References
- github.com/mckaywrigley/chatbot-ui (product)
- github.com/mckaywrigley/chatbot-ui/blob/81328b61d2a4ab597a7a057be70e785cf756d9f… (technical-description)
- github.com/mckaywrigley/chatbot-ui/issues/2028 (issue-tracking)
- www.vulncheck.com/advisories/chatbot-ui-cross-user-private-file-content-disclos… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-85693?
- CVE-2026-85693 is a medium-severity vulnerability in Mckaywrigley Chatbot-Ui, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-09-04.
- How severe is CVE-2026-85693?
- Medium severity. CVSS v3 base score is 6.5 out of 10.