| Component | Open WebUI |
| Severity | high (CVSS 8.1) |
| CVSS vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| Published (NVD) | 2026-05-15 |
| Last modified | 2026-06-18 |
| Affected versions | open_webui < 0.9.0 |
| Fixed in | 0.9.0 |
| Weakness | CWE-269CWE-362 |
| CISA KEV | not listed |
NVD description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the LDAP and OAuth authentication flows use a TOCTOU (Time-of-Check-Time-of-Use) pattern for first-user admin role assignment. The regular signup handler (signup_handler in auths.py, line 663) was explicitly patched to prevent this race with the comment "Insert with default role first to avoid TOCTOU race", but the LDAP and OAuth code paths were never updated with the same fix. This vulnerability is fixed in 0.9.0.
What to do
- Upgrade Open WebUI to
0.9.0or later. - Do not expose the component's API or UI to the internet without authentication in front of it.
Sources
- NVD: CVE-2026-45675
- https://github.com/open-webui/open-webui/security/advisories/GHSA-h3ww-q6xx-w7x3
- https://github.com/open-webui/open-webui/commit/96a0b3239b1aadb23fc359bf10849c9ba12fd6ec
- https://github.com/open-webui/open-webui/pull/23626
Read more
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