CVE-2026-42266
JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. From 4.0.0 to 4.5.6, the allow-list of extensions that can be installed from PyPI Extension Manager (allowed_extensions_uris) is not correctly enforced by JupyterLab. The PyPI Extension Manager was not contained to packages listed on the default PyPI index. This vulnerability is fixed in 4.5.7.
- Score
- CVSS 3.1 8.8 High
- Status
- Modified - security-advisories@github.com
- Published
- 2026-05-13
- Last modified
- 2026-08-28
- Weaknesses
- CWE-602, CWE-88
Affected products
- Jupyterlab (Jupyter)
- Jupyterlab (Jupyterlab)
- Migration Toolkit Applications (Redhat)
- Openshift Ai (Redhat)
References
- https://github.com/jupyterlab/jupyterlab/releases/tag/v4.5.7
- https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-37w4-hwhx-4rc4
- https://jupyterhub.readthedocs.io/en/5.2.1/explanation/websecurity.html
- https://jupyterlab.readthedocs.io/en/latest/user/extensions.html#extension-manager-implementations
- https://access.redhat.com/errata/RHSA-2026:43038
- https://access.redhat.com/errata/RHSA-2026:60520
- https://access.redhat.com/security/cve/CVE-2026-42266
- https://bugzilla.redhat.com/show_bug.cgi?id=2477072
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42266.json
