Bug 2509997 (CVE-2026-67338)

Summary: CVE-2026-67338 jupyterlab: JupyterLab: Stored cross-site scripting in Extension Manager allows arbitrary code execution
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rjohnson
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in JupyterLab. The Extension Manager fails to validate URI protocols in package metadata URLs. This allows attackers to publish malicious PyPI packages containing `javascript:` URLs in their project metadata. When a user clicks on the extension name, arbitrary JavaScript code can be executed within the JupyterLab environment, potentially leading to information disclosure or unauthorized actions.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2511389, 2511390, 2511424, 2511425    
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Description OSIDB Bzimport 2026-08-01 13:02:26 UTC
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.