CVE-2026-67338

Description

JupyterLab before 4.5.9 contains a stored cross-site scripting vulnerability in the Extension Manager that fails to validate URI protocols in package metadata URLs. Attackers can publish malicious PyPI packages with javascript: URLs in project metadata that execute arbitrary JavaScript in the JupyterLab origin when users click the extension name.

CVSS Vector

References

• https://github.com/jupyterlab/jupyterlab/commit/4e61e07d0a91145b53fbf96ac74b0387f6bc51f6
• https://github.com/jupyterlab/jupyterlab/commit/d5d961f6e10a6442dddbf94d9a976b3897055a12
• https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-vmhf-c436-hxj4
• https://www.vulncheck.com/advisories/jupyterlab-before-stored-xss-via-extension-manager