Auth bypass in Open-Webui
CVE-2026-109296
Open WebUI before 0.11.4 contains a missing authorization vulnerability that allows authenticated users to reach disabled model provider backends by supplying an explicit backend index. Attackers can pass the index as a path segment or query parameter on Ollama and OpenAI-compatible listing routes to trigger requests carrying configured API keys, read version strings, and enumerate connections.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published .
CVSS v3 metric
CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/open-webui/open-webui/security/advisories/GHSA-hm62-64q2-6gxw (vendor-advisory)
- www.vulncheck.com/advisories/open-webui-before-0.11.4-missing-authorization-via… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-109296?
- CVE-2026-109296 is a medium-severity vulnerability in Open-Webui, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-10-12.
- How severe is CVE-2026-109296?
- Medium severity. CVSS v3 base score is 4.3 out of 10.