CVE-2026-102830Medium· 6.8▾ SunlitJupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. From JupyterLab 3.0.0 until 4.5.11 and 4.6.4, and in JupyterLite Core 0.8.3 and earlier, the Plural-Forms hea…
▾ Sunlit zone — Low / medium · no exploitation signal
impact 37.4 · likelihood 0.1 · exploitation 0
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Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake.
Exploit-prediction probability, daily snapshots since Sep 30.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.3%
JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. From JupyterLab 3.0.0 until 4.5.11 and 4.6.4, and in JupyterLite Core 0.8.3 and earlier, the Plural-Forms header in a selected third-party language pack can append JavaScript after a valid plural rule because prefix-only regular-expression validation accepts a matching prefix without requiring the entire header to match. JupyterLab passes the accepted expression to new Function, so loading the catalogue and translating a plural string executes the appended code in the authenticated JupyterLab origin. Where Jupyter Server kernels, terminals, and APIs are exposed, the code can use authenticated server APIs to read or modify files and run code. Impact is much more limited in JupyterLite because it typically lacks most exposed Jupyter Server surfaces. The default English locale is unaffected because it does not load a translation catalogue. This issue is fixed in JupyterLab 4.5.11 and 4.6.4 and JupyterLite Core 0.8.4.
Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Affected packages:
jupyterlab >= 4.6.0, <= 4.6.3jupyterlab >= 3.0.0, <= 4.5.10jupyterlite-core <= 0.8.3Patched in:
jupyterlab 4.6.4jupyterlab 4.5.11jupyterlite-core 0.8.4Connected by shared product, vendor, weakness, or advisory.
CVE-2026-102831High· 8.1JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture
CVE-2026-102904Medium· 5.4JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture
CVE-2026-102832Medium· 4.2JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture
CVE-2026-73417High· 8.3jupyterlab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture
CVE-2026-67338Medium· 6.1JupyterLab 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
CVE-2026-73626High· 7.5JupyterLab versions >=4.6.0,<=4.6.1 and <=4.5.9 contain an allowlist/blocklist enforcement gap in PyPIExtensionManager.install()