Vulnerability 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 Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Openwebui | Open Webui | < 0.9.6 |
Related Weaknesses (CWE)
References
- https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvvExploitMitigationVendor Advisory
- https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvvExploitMitigationVendor Advisory
FAQ
What is CVE-2026-54011?
CVE-2026-54011 is a vulnerability with a CVSS score of 8.7 (HIGH). 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 in...
How severe is CVE-2026-54011?
CVE-2026-54011 has been rated HIGH with a CVSS base score of 8.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-54011?
Check the references section above for vendor advisories and patch information. Affected products include: Openwebui Open Webui.