Vulnerability · Published Oct 12, 2026 · Assigned by VulnCheck
CVE-2026-109288Open WebUI before 0.11.4 Stored XSS via javascript: URLs in Markdown Links
Medium 6.4
In plain English
A medium-severity cross-site scripting in open-webui from open-webui. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities).
Severity (CVSS 3.1)6.4Medium
Exploit odds (30 days)0.3%top 78.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
Open WebUI before 0.11.4 contains a stored cross-site scripting vulnerability in MarkdownInlineTokens.svelte, which renders markdown link URLs into anchor hrefs without validating their scheme. Authenticated users can embed javascript: links in shared chats that, when clicked by a victim, steal the victim's JWT from local storage, including admins' tokens.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| open-webui | open-webui | 0 – before 0.11.4 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
References
- GitHub Security Advisory (GHSA-wf9m-46cp-c6h6) vendor-advisory
- VulnCheck Advisory: Open WebUI before 0.11.4 Stored XSS via javascript: URLs in Markdown Links third-party-advisory