CVE-2026-54011

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 v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvv	Exploit Mitigation Vendor Advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvv	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*

History

25 Jun 2026, 13:33

Type	Values Removed	Values Added
References	~~() https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvv -~~	() https://github.com/open-webui/open-webui/security/advisories/GHSA-v8qj-hxv7-mgvv - Exploit, Mitigation, Vendor Advisory
CPE		cpe:2.3:a:openwebui:open_webui::::::::
First Time		Openwebui open Webui Openwebui

23 Jun 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-23 18:18

Updated : 2026-06-25 13:33

NVD link : CVE-2026-54011

Mitre link : CVE-2026-54011

CVE.ORG link : CVE-2026-54011

JSON object : View

Products Affected

openwebui

open_webui

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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