Disclosure summary
JupyterLab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. From JupyterLab 4.5.0 until 4.5.11 and 4.6.4, from Notebook 7.5.0 until 7.6.3, and from JupyterLite Core 0.7.0 until 0.8.4, the system clipboard cell-paste path accepts attacker-controlled cell JSON without clearing metadata.trusted. When useSystemClipboardForCells is active and pasteCodeCellsWithoutOutput is disabled, a pasted code cell can mark HTML output as trusted, bypass output sanitization, and execute script in the authenticated JupyterLab origin without executing the cell. Markdown and raw cells are not affected because their output is sanitized. This issue is fixed in JupyterLab 4.5.11 and 4.6.4, Notebook 7.6.3, and JupyterLite Core 0.8.4.
Source-reported weakness categories
CWE-79, CWE-345
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
NIST National Vulnerability Database · NVD-CVE-2026-102831
Open original source · Updated Oct 02, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
GitHub Reviewed Security Advisories · GHSA-6966-vjj6-99xv
Open original source · Updated Oct 01, 2026
JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard
Source severity: HIGH / 0
| Ecosystem | Package | Affected range | First patched |
|---|---|---|---|
| pip | jupyterlab | >= 4.6.0, | 4.6.4 |
| pip | jupyterlab | >= 4.5.0, | 4.5.11 |
| pip | notebook | >= 7.5.0, | 7.6.3 |
| pip | jupyterlite | >= 0.7.0, | 0.8.4 |
| pip | jupyterlite-core | >= 0.7.0, | 0.8.4 |
Original records & references
PUBLISHED 2026-09-29T15:17:25-04:00
MODIFIED 2026-10-02T09:17:27-04:00
INGESTED 2026-10-06T11:43:05-04:00