8.8highHigh
CVE-2026-42266
Jupyter Jupyterlab
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.
Exploitation status
- A vendor advisory or patch reference has been published.
What the metrics mean
- It is reachable over a network, without needing local access.
- For an attacker who can reach it, no special conditions are needed to exploit it.
- To exploit it, an ordinary user account is needed.
- Beyond that, no action by a user is required.
Scoring
- CVSS
- 8.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-88
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-05-13
- Last modified
- 2026-08-28
- Sources
- NVD
Affected products
- Jupyter Jupyterlab4.0.0 - 4.5.7
As listed in the NVD configuration data. Not a statement about your estate.
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