CVE-2026-70486

What it is

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.0 until 0.11.0, the terminal file-preview serveUrl iframe branch always granted allow-same-origin together with allow-scripts for HTML files served from the application origin. Any authenticated user with access to a configured terminal server could cause script in a previewed file to run in the Open WebUI origin, read the victim's session token from localStorage, and take over the account, with possible server-side code execution if the victim was an admin or held workspace.functions. This issue is fixed in 0.11.0.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure, data tampering.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-08-04 20:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-18 14:46 UTC Last updatedMost recent change to the record

Details

Published

2026-08-04 20:16 UTC

Last modified

2026-09-18 14:46 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-79 · Cross-site scripting

Record status

Analyzed

Affected

• Openwebui Open Webui < 0.11.0

Attack profile CVSS 3.1 · 8.2

Attack vector

Network

Complexity

High

Privileges needed

Low

User interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

None