Missing Authorization in Open WebUI - CVE-2026-59714

 

Missing Authorization in Open WebUI - CVE-2026-59714

Published: July 3, 2026 / Updated: August 16, 2026


Vulnerability identifier: #VU136843
CSH Severity: Low
CVSS v4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-59714
CWE-ID: CWE-862
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to overwrite messages in channels they do not belong to.

The vulnerability exists due to improper access control in the chat completion API channel pipeline when handling chat completion requests with a channel:-prefixed chat_id and attacker-controlled message_id values. A remote user can send a specially crafted chat completion request to overwrite messages in channels they do not belong to.

The overwritten message retains the original author attribution while displaying attacker-controlled content, including in private and direct-message channels.


Affected software

Open WebUI

How to mitigate CVE-2026-59714

Install security update from vendor's website.

Open WebUI - update to 0.10.0

External References

Related Security Bulletins