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CVE-2026-42266

JupyterLab has an Extension Manager API/GUI Policy Discrepancy allowing 3rd party (malicious) extensions install via POST request.

Published: May 13, 2026Updated: Jul 22, 2026 Sources: CVE List NVDCWE-88
8.8HIGH
NVD MITRE
EPSS Score
0.6%
Top 56.8%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
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Weaknesses

CWE-88CWE-602

Affected Products

jupyter
oss-projectaka notebook, jupyter server, jupyterlab
jupyterlabOn-premWeb App
AI / ML / notebook-mlops
jupyterlab
oss-projectaka jupyter lab
jupyterlabOn-prem
DevTools & CI / ide-editor

Exploitability

Official Patch Available
Workaround Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Execution
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References

https://github.com/jupyterlab/jupyterlab/releases/tag/v4.5.7
github.com
https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-37w4-hwhx-4rc4
github.com
https://jupyterhub.readthedocs.io/en/5.2.1/explanation/websecurity.html
jupyterhub.readthedocs.io
and 5 more references View all →

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