Advisories for Pypi/Nicegui package

XSS risk exists 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 …

An unauthenticated attacker can exhaust Redis connections by repeatedly opening and closing browser tabs on any NiceGUI application using Redis-backed storage. Connections are never released, leading to service degradation when Redis hits its connection limit. NiceGUI continues accepting new connections - errors are logged but the app stays up with broken storage functionality.

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.

An unsafe implementation in the click event listener used by ui.sub_pages, combined with attacker-controlled link rendering on the page, causes an XSS when the user actively clicks on the link.

A directory traversal vulnerability in NiceGUI's App.add_media_files() allows a remote attacker to read arbitrary files on the server filesystem.

A Cross-Site Scripting (XSS) vulnerability exists in the ui.interactive_image component of NiceGUI (v3.3.1 and earlier). The component renders SVG content using Vue's v-html directive without any sanitization. This allows attackers to inject malicious HTML or JavaScript via the SVG <foreignObject> tag.

A Cross-Site Scripting (XSS) vulnerability exists in ui.add_css, ui.add_scss, and ui.add_sass functions in NiceGUI (v3.3.1 and earlier). These functions allow developers to inject styles dynamically. However, they lack proper sanitization or encoding for the JavaScript context they generate. An attacker can break out of the intended <style> or <script> tags by injecting closing tags (e.g., </style> or </script>), allowing for the execution of arbitrary JavaScript.

A Cross-Site Scripting (XSS) risk exists in NiceGUI when developers render unescaped user input into the DOM using ui.html(). Before version 3.0, NiceGUI does not enforce HTML or JavaScript sanitization, so applications that directly combine components like ui.input() with ui.html() without escaping may allow attackers to execute arbitrary JavaScript in the user’s browser. Same holds for ui.chat_message with HTML content. Applications that directly reflect user input via ui.html() (or ui.chat_message …

Once a user logins to one browser, all other browsers are logged in without entering password. Even incognito mode.

NiceGUI is an easy-to-use, Python-based UI framework. A local file inclusion is present in the NiceUI leaflet component when requesting resource files under the /_nicegui/{version}/resources/{key}/{path:path} route. As a result any file on the backend filesystem which the web server has access to can be read by an attacker with access to the NiceUI leaflet website. This vulnerability has been addressed in version 1.4.21. Users are advised to upgrade. There are …