zauberzeug nicegui up to 2.x ui.html cross site scripting

Summaryinfo

A vulnerability has been found in zauberzeug nicegui up to 2.x and classified as problematic. Affected by this issue is the function ui.html. The manipulation leads to cross site scripting. This vulnerability is uniquely identified as CVE-2025-53354. The attack is possible to be carried out remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in zauberzeug nicegui up to 2.x. It has been rated as problematic. This issue affects the function ui.html. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. The summary by CVE is:

NiceGUI is a Python-based UI framework. Versions 2.24.2 and below are at risk for Cross-Site Scripting (XSS) when developers render unescaped user input into the DOM using ui.html(). NiceGUI did not enforce HTML or JavaScript sanitization, so applications that directly combine components like ui.input() with ui.html() or ui.chat_message with HTML content without escaping may allow attackers to execute arbitrary JavaScript in the user’s browser. Applications that do not pass untrusted input into ui.html() are not affected. This issue is fixed in version 3.0.0.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2025-53354 since 06/27/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 3.0.0 eliminates this vulnerability. Applying the patch 4673dc35c94a0c7339e2164378b0977332e60775 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Vendor

• zauberzeug

Name

• nicegui

Version

• 2.x

License

• open-source

Website

• Product: https://github.com/zauberzeug/nicegui/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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