CVE-2026-42266
8.8 · HIGHOverview
CVE-2026-42266 is a high-severity vulnerability affecting jupyter jupyterlab. It was published on May 13, 2026 and has a CVSS 3.1 base score of 8.8 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from jupyter. Update jupyterlab to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| jupyter | jupyterlab | >= 4.0.0, < 4.5.7 | Affected |
References
Frequently Asked Questions
What is CVE-2026-42266?
CVE-2026-42266 is a high-severity vulnerability affecting jupyter jupyterlab. It was published on May 13, 2026 and has a CVSS 3.1 base score of 8.8 (HIGH).
How severe is CVE-2026-42266?
This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-42266?
Check the references section for vendor advisories and patches from jupyter. Update jupyterlab to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-42266?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-42266 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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