# CVE-2026-42266: jupyterlab: JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Arc...

CVE-2026-42266 is fixed in jupyterlab on 1 platform by DEBIAN-CVE-2026-42266 (version 4.4.10+ds1+~3.1.0+~0.16.6+~cs1.4.4-3), released May 13, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-42266
- Priority: High
- CVSS: 8.8 (high)
- EPSS: 0.0565
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 13, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | jupyterlab Debian 14 | 4.4.10+ds1+~3.1.0+~0.16.6+~cs1.4.4-3 | [DEBIAN-CVE-2026-42266](https://patchblox.com/security/data/fix/linux/debian-cve-2026-42266.md) | May 13, 2026 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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