Missing Authorization in Open WebUI - CVE-2026-70481
Published: August 3, 2026
Vulnerability identifier: #VU140750
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-70481
CWE-ID: CWE-862
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to modify or delete other users' messages in a standard channel.
The vulnerability exists due to missing authorization in update_message_by_id and delete_message_by_id in backend/open_webui/routers/channels.py when handling update and delete requests for standard-channel messages. A remote user can send crafted requests referencing another member's message ID to modify or delete other users' messages in a standard channel.
Only standard channels are affected, and channels must be enabled. Group and direct message channels are not affected.
Affected software
Open WebUI
How to mitigate CVE-2026-70481
Install security update from vendor's website.
Open WebUI - update to 0.11.0