Medium severity · published Oct 12, 2026
CVE-2026-109288
Open WebUI before 0.11.4 Stored XSS via javascript: URLs in Markdown Links
6.4
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 22% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
open-webui · open-webui
before 0.11.4 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-109288
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-109288
vendor-advisory
https://github.com/open-webui/open-webui/security/advisories/GHSA-wf9m-46cp-c6h6
third-party-advisory
https://www.vulncheck.com/advisories/open-webui-before-0.11.4-stored-xss-via-javascript-urls-in-markdown-links
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