CVE-2026-42557

jupyterlab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. Prior to 4.5.7, JupyterLab's HTML sanitizer allowlists data-commandlinker-command and data-commandlinker-args on button elements, while CommandLinker listens for all cli...

Cross-site Scripting (XSS)

JupyterLab is vulnerable to Cross-site Scripting XSS. The vulnerability is due to insufficient validation of data-commandlinker- attributes in sanitized HTML output, which allows an attacker to craft a malicious notebook containing a deceptive button that executes arbitrary JupyterLab commands,...

JupyterLab's command linker attributes in HTML enable one-click command execution from untrusted content

JupyterLab's HTML sanitizer allowlists data-commandlinker-command and data-commandlinker-args on button elements, while CommandLinker listens for all click events on document.body and executes the named command without checking whether the element came from trusted JupyterLab UI. A notebook with ...

Cross-site Scripting (XSS)

Overview @jupyterlab/help-extension is a JupyterLab - Help Extension Affected versions of this package are vulnerable to Cross-site Scripting XSS via the handling of data-commandlinker-command and data-commandlinker-args attributes in HTML content. An attacker can execute arbitrary commands,...

Cross-site Scripting (XSS)

Overview @jupyterlab/markdownviewer-extension is a JupyterLab - Markdown Renderer Extension Affected versions of this package are vulnerable to Cross-site Scripting XSS via the handling of data-commandlinker-command and data-commandlinker-args attributes in HTML content. An attacker can execute...

Cross-site Scripting (XSS)

Overview @jupyterlab/notebook is a JupyterLab - Notebook Affected versions of this package are vulnerable to Cross-site Scripting XSS via the handling of data-commandlinker-command and data-commandlinker-args attributes in HTML content. An attacker can execute arbitrary commands, including code...

Cross-site Scripting (XSS)

Overview @jupyterlab/rendermime-extension is an A rendermime extension for JupyterLab Affected versions of this package are vulnerable to Cross-site Scripting XSS via the handling of data-commandlinker-command and data-commandlinker-args attributes in HTML content. An attacker can execute arbitra...

Cross-site Scripting (XSS)

Overview @jupyterlab/rendermime is a JupyterLab - RenderMime Affected versions of this package are vulnerable to Cross-site Scripting XSS via the handling of data-commandlinker-command and data-commandlinker-args attributes in HTML content. An attacker can execute arbitrary commands, including co...