MEDIUMCVSS 6.1
CVE-2025-66469
CVE-2025-66469 updated by NVD
Summary
NiceGUI is a Python-based UI framework. Versions 3.3.1 and below are vulnerable to Reflected XSS through its ui.add_css, ui.add_scss, and ui.add_sass functions. The functions lack proper sanitization or encoding for the JavaScript context they generate. An attacker can break out of the intended or tags by injecting closing tags (e.g., or ), allowing for the execution of arbitrary JavaScript. This issue is fixed in version 3.4.0.
References
Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.
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