CVE-2026-67338
JupyterLab before 4.5.9 Stored XSS via Extension Manager
- State
- Published
- Severity
- 5.1 Medium
- Published
- Aug 1, 2026
- Updated
- Oct 8, 2026
- Reserved
- Jul 29, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.1 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N | VulnCheck |
| 3.1 | 6.1 Medium | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N | VulnCheck |
Weaknesses
- CWE-84 Improper Neutralization of Encoded URI Schemes in a Web Page
Affected Products
| Product | Versions |
|---|---|
jupyterlabjupyterlab |
|
References
- GitHub Security Advisory (GHSA-vmhf-c436-hxj4)vendor-advisory
- Patch Commitpatch
- Patch Commitpatch
- VulnCheck Advisory: JupyterLab before 4.5.9 Stored XSS via Extension Managerthird-party-advisory
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