What is CVE-2026-109291?

CVE-2026-109291 is a high-severity vulnerability in Open-Webui, classified under Cross-site Scripting. CVSS score: 7.3/10. Published 2026-10-12.

How severe is CVE-2026-109291?

High severity. CVSS v3 base score is 7.3 out of 10.

XSS in Open-Webui

CVE-2026-109291

Open WebUI from 0.6.33 before 0.11.4 contains a cross-site scripting vulnerability that allows authenticated users to execute script in victims' sessions by storing javascript: URLs in citation embed_url fields. Attackers can share a crafted chat whose citation, when clicked, is passed to window.open, letting them steal localStorage.token and act as the victim.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-10-12.

CVSS v3 metric

CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Open-Webui

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/open-webui/open-webui/security/advisories/GHSA-qpqv-xwg8-cqpj (vendor-advisory)
www.vulncheck.com/advisories/open-webui-0.6.33-before-0.11.4-stored-xss-via-cit… (third-party-advisory)

Frequently asked questions

What is CVE-2026-109291?: CVE-2026-109291 is a high-severity vulnerability in Open-Webui, classified under Cross-site Scripting. CVSS score: 7.3/10. Published 2026-10-12.
How severe is CVE-2026-109291?: High severity. CVSS v3 base score is 7.3 out of 10.