Cross-site scripting in Open WebUI - CVE-2026-26193
Published: April 24, 2026
Vulnerability identifier: #VU127473
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-26193
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Open WebUI
Affected software:
Open WebUI
Open WebUI
Detailed vulnerability description
The vulnerability allows a remote user to execute arbitrary script in a victim's browser.
The vulnerability exists due to cross-site scripting in the ResponseMessage.svelte iFrame embed handling when rendering user-controlled response message embeds. A remote user can modify chat history to inject a crafted embeds value to execute arbitrary script in a victim's browser.
User interaction is required to view the affected chat or a shared chat link.
How to mitigate CVE-2026-26193
Install security update from vendor's website.