CVE-2026-45675 Open WebUI: LDAP and OAuth First-User Race Condition Allows Multiple Admin Accounts

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, he 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 signuphandler in auths.py, line...

CVE-2026-45675

Open WebUI CVE-2026-45675 describes a TOCTOU race in first-user admin role assignment for LDAP and OAuth paths prior to version 0.9.0. The signup path was fixed to insert with a default role first and upgrade if only one user remains; LDAP and OAuth paths did not receive that fix. Attack scenario...

PT-2026-41203

Name of the Vulnerable Software and Affected Versions Open WebUI versions prior to 0.9.0 Description LDAP and OAuth authentication flows use a Time-of-Check-Time-of-Use TOCTOU pattern—a race condition where a system checks a condition and then uses the result of that check, but the condition...