CVE-2026-44558 MEDIUM

CVE-2026-44558: Open WebUI: Channel Access Grants Bypass filter_allowed_access_grants

Vendor Open-Webui
Product open-webui
Weakness CWE-862 · Missing authorization
Published May 15, 2026
Last update May 19, 2026

CVSS base score

5.4/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality Low
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

What the vulnerability does

01Description

Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.0, the channel router does not call filter_allowed_access_grants on either create or update paths. A non-admin user who can create group channels (or who owns a channel) can submit arbitrary access grants — including public wildcard grants — and those grants are stored verbatim, bypassing the admin's permission framework. This vulnerability is fixed in 0.9.0.

Key dates

02Disclosure timeline

May 15, 2026 CVE published
May 19, 2026 Record updated