CVE-2026-87995: Open WebUI: Same-origin XSS to account takeover via terminal port-preview iframe hardcoding allow-same-origin
Any authenticated user with access to a shared terminal server could get script of their choosing to run in the Open WebUI origin itself. The in-app port preview rendered the content of a previewed port in an iframe whose sandbox always granted allow-same-origin alongside allow-scripts, and that content is served from a path on the application’s own origin, so the sandbox provided no isolation at all. Script served on a previewed port could read the victim’s session token and take over the account.
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Code Behaviors & Features
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