Incorrect authorization in Open WebUI - CVE-2026-45339
Published: May 11, 2026
Vulnerability identifier: #VU130940
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-45339
CWE-ID: CWE-863
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass endpoint restrictions and access restricted API functionality.
The vulnerability exists due to incorrect authorization in the API key endpoint restriction check when authenticating requests with the x-api-key header. A remote privileged user can send a request with a valid API key in the x-api-key header to bypass endpoint restrictions and access restricted API functionality.
The issue affects requests to the Anthropic-compatible API path, where the restriction check is applied to Authorization headers but skipped for the same key presented in x-api-key.
Affected software
Open WebUI
How to mitigate CVE-2026-45339
Install security update from vendor's website.
Open WebUI - update to 0.9.0