CVE-2026-21871 (GCVE-0-2026-21871)
Vulnerability from cvelistv5 – Published: 2026-01-08 09:49 – Updated: 2026-01-08 15:15
VLAI
EPSS
VEX
Title
NiceGUI is vulnerable to XSS via Unescaped URL in ui.navigate.history.push() / replace()
Summary
NiceGUI is a Python-based UI framework. From versions 2.13.0 to 3.4.1, there is a XSS risk in NiceGUI when developers pass attacker-controlled strings into ui.navigate.history.push() or ui.navigate.history.replace(). These helpers are documented as History API wrappers for updating the browser URL without page reload. However, if the URL argument is embedded into generated JavaScript without proper escaping, a crafted payload can break out of the intended string context and execute arbitrary JavaScript in the victim’s browser. Applications that do not pass untrusted input into ui.navigate.history.push/replace are not affected. This issue has been patched in version 3.5.0.
Severity
6.1 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-08 15:14 UTC
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/zauberzeug/nicegui/security/ad… | x_refsource_CONFIRM |
| https://github.com/zauberzeug/nicegui/releases/ta… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| zauberzeug | nicegui |
Affected:
>= 2.13.0, < 3.5.0
|
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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