Cross-site Scripting (XSS) Affecting jupyterlab package, versions <4.4.10+ds1+~3.1.0+~0.16.6+~cs1.4.4-3


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.35% (28th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-JUPYTERLAB-16748161
  • published18 May 2026
  • disclosed13 May 2026

Introduced: 13 May 2026

CVE-2026-42557  (opens in a new tab)
CWE-79  (opens in a new tab)

How to fix?

Upgrade Debian:unstable jupyterlab to version 4.4.10+ds1+3.1.0+0.16.6+~cs1.4.4-3 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream jupyterlab package and not the jupyterlab package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

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 click events on document.body and executes the named command without checking whether the element came from trusted JupyterLab UI. A notebook with a pre-saved HTML cell output containing a deceptive button can trigger arbitrary JupyterLab commands - including arbitrary code execution - on a single user click, without any code being submitted for execution by the user. This vulnerability is fixed in 4.5.7.

CVSS Base Scores

version 3.1