JupyterLab has an Extension Manager API/GUI Policy Discrepancy allowing 3rd party (malicious) extensions install via POST request. (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.
JupyterLab has an Extension Manager API/GUI Policy Discrepancy allowing 3rd party (malicious) extensions install via POST request. (CVE-2026-42266)
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.
Affected software
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Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BIT-jupyterlab-2026-42266
- Osv Schema Version
- 1.6.2
- Aliases
- ["CVE-2026-42266"]
- Ecosystems
- ["Bitnami"]
- Database Specific Severity
- High
Threat ID: 6a4c347727e9c79719604232
Added to database: 07/06/2026, 23:04:23 UTC
Last enriched: 07/06/2026, 23:37:40 UTC
Last updated: 09/10/2026, 19:36:54 UTC
Views: 79
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