CVE-2026-45675

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/commit/96a0b3239b1aadb23fc359bf10849c9ba12fd6ec	Patch
https://github.com/open-webui/open-webui/pull/23626	Issue Tracking
https://github.com/open-webui/open-webui/security/advisories/GHSA-h3ww-q6xx-w7x3	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-15 20:16

Updated : 2026-06-18 22:16

NVD link : CVE-2026-45675

Mitre link : CVE-2026-45675

CVE.ORG link : CVE-2026-45675

JSON object : View

Products Affected

openwebui

open_webui

CWE

CWE-269

Improper Privilege Management

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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