CVE-2026-54011
HIGH EPSS 10.0%
Published Jun 23, 20261w ago · Modified Jun 23, 20261w ago
8.7 CVSS 3.1
Published Jun 23, 2026 1w ago
Last Modified Jun 23, 2026 1w ago
Description
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.6,Open WebUI renders Mermaid blocks from Markdown files in the file preview panel and inserts the generated SVG into the DOM using innerHTML. Because Mermaid is configured with securityLevel: 'loose', attacker-controlled Mermaid content can be rendered unsafely in this flow. A working payload was validated through the Markdown preview path, resulting in JavaScript execution in the victim’s browser under the application origin. This vulnerability is fixed in 0.9.6.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction Required
Scope Changed
Confidentiality High
Integrity High
Availability None
Threat Intelligence
EPSS Exploit Probability
10.0% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-79 Cross-site Scripting Injection
References 1
- github.com https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvv
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.