NiceGUI apps which use `ui.sub_pages` vulnerable to zero-click XSS

SummaryAn unsafe implementation in the pushstate event listener used by ui.subpages allows an attacker to manipulate the fragment identifier of the URL, which they can do despite being cross-site, using an iframe. DetailsThe problem is traced as follows:1. On pushstate, handleStateEvent is...

EUVD-2026-1475

NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the pushstate event listener used by ui.subpages allows an attacker to manipulate the fragment identifier of the URL, which they can do despite being cross-site, using an iframe. This issue has been...