CVE-2026-70486: Open WebUI: Same-origin XSS to account takeover via terminal file-preview iframe hardcoding allow-same-origin
Any authenticated user with access to a terminal server could get script of their choosing to run in the Open WebUI origin itself. The HTML file preview rendered terminal-served files in an iframe whose sandbox always granted allow-same-origin alongside allow-scripts, and the file is served from a path on the application’s own origin, so the sandbox provided no isolation at all. Script in a previewed file could read the victim’s session token and take over the account.
References
- github.com/advisories/GHSA-3xpf-xq7r-v8c5
- github.com/open-webui/open-webui/commit/65a5fad7b97db99d490d81f4e0860282c3a4543c
- github.com/open-webui/open-webui/pull/26907
- github.com/open-webui/open-webui/releases/tag/v0.11.0
- github.com/open-webui/open-webui/security/advisories/GHSA-3xpf-xq7r-v8c5
- nvd.nist.gov/vuln/detail/CVE-2026-70486
Code Behaviors & Features
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