Cross-Site Scripting Vulnerability in Open WebUI Affects Multiple Versions
CVE-2026-109291

8.5HIGH

Key Information:

Vendor

Open-webui

Status
Open-webui
Vendor
CVE Published:
12 October 2026

What is CVE-2026-109291?

Open WebUI versions prior to 0.11.4 have a vulnerability that permits authenticated users to execute arbitrary JavaScript in other users' sessions. This vulnerability arises from storing malicious JavaScript URLs in citation embed_url fields. When an attacker shares a crafted chat that includes a harmful citation, it can exploit the window.open functionality, enabling the attacker to access the victim's local storage token. This flaw has serious implications for user data security and application integrity.

Affected Version(s)

open-webui 0.6.33 < 0.11.4

open-webui 0.11.4

References

https://github.com/open-webui/open-webui/security/advisor...
vendor-advisory
https://www.vulncheck.com/advisories/open-webui-0.6.33-be...
third-party-advisory

CVSS V4

Score:
8.5
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

zyakir13
Classic298
.