CVE-2026-21872: medium-severity vulnerability in zauberzeug nicegui
NiceGUI apps are vulnerable to XSS which uses `ui.sub_pages` and render arbitrary user-provided links
Published
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.1epss 0.3%
NiceGUI is a Python-based UI framework. From versions 2.22.0 to 3.4.1, an unsafe implementation in the click event listener used by ui.sub_pages, combined with attacker-controlled link rendering on the page, causes XSS when the user actively clicks on the link. This issue has been patched in version 3.5.0.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected products
zauberzeug · niceguiRelated CVEs — zauberzeug nicegui
In the same product, most dangerous first.
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