CVE-2026-21873 (GCVE-0-2026-21873)

Vulnerability from cvelistv5 – Published: 2026-01-08 09:50 – Updated: 2026-01-08 15:11
VLAI?
Title
Zero-click XSS in all NiceGUI apps which uses `ui.sub_pages`
Summary
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.sub_pages 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 patched in version 3.5.0.
Severity ?
7.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
zauberzeug nicegui Affected: >= 2.22.0, < 3.5.0
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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