Improper Authorization in Open WebUI - CVE-2026-45365
Published: May 11, 2026
Vulnerability identifier: #VU130947
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-45365
CWE-ID: CWE-285
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass model access control and invoke restricted models.
The vulnerability exists due to improper authorization in the /openai/chat/completions and /ollama/api/chat HTTP endpoints when handling requests with the exposed bypass_filter query parameter. A remote user can append ?bypass_filter=true to a request URL to bypass model access control and invoke restricted models.
The issue affects the FastAPI route handlers generate_chat_completion in routers/openai.py and routers/ollama.py, where an internal-only parameter is bound from the query string.
Affected software
Open WebUI
How to mitigate CVE-2026-45365
Install security update from vendor's website.
Open WebUI - update to 0.8.11