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CVE-2026-45339
Published:May 15, 2026
Updated:May 18, 2026
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, Open WebUI allows admins to restrict which API endpoints an API key can access. When an API key is restricted from /api/v1/messages, requests using the Authorization: Bearer sk-... header are correctly blocked with 403. However, the same key sent via the x-api-key header bypasses the restriction entirely — the request is authenticated, the model is invoked, and a full response is returned. This vulnerability is fixed in 0.9.0.
Affected Packages
https://github.com/open-webui/open-webui.git (GITHUB):
Affected version(s) >=v0.1.102 <v0.9.0
Fix Suggestion:
Update to version v0.9.0
open-webui (PYTHON):
Affected version(s) >=0.1.124 <0.9.0
Fix Suggestion:
Update to version 0.9.0
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CVSS v4
Base Score:
8.5
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
HIGH
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Incorrect Authorization
EPSS
Base Score:
0.03