Protection mechanism failure in Open WebUI - CVE-2026-59223

 

Protection mechanism failure in Open WebUI - CVE-2026-59223

Published: July 3, 2026


Vulnerability identifier: #VU136849
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-59223
CWE-ID: CWE-693
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to disclose sensitive information from administrator-blocked publicly resolvable hosts.

The vulnerability exists due to protection mechanism failure in WEB_FETCH_FILTER_LIST hostname filtering when processing server-side web fetch URLs. A remote user can trigger a server-side web fetch using a crafted URL to disclose sensitive information from administrator-blocked publicly resolvable hosts.

The issue affects the allow/block list used by RAG URL ingestion, URL-to-markdown, and web-search content fetch. Fetched content is returned to the requester. This issue does not bypass the separate always-on guard that blocks URLs resolving to non-global IP addresses when local web fetch is disabled, which is the default.


Affected software

Open WebUI

How to mitigate CVE-2026-59223

Install security update from vendor's website.

Open WebUI - update to 0.10.0

External References

Related Security Bulletins