CVE-2026-67338

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 v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-01 13:17

Updated : 2026-09-09 20:36

NVD link : CVE-2026-67338

Mitre link : CVE-2026-67338

CVE.ORG link : CVE-2026-67338

JSON object : View

Products Affected

No product.

CWE

CWE-84

Improper Neutralization of Encoded URI Schemes in a Web Page

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