CVE-2026-102831 · GHSA-6966-vjj6-99xv
JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard
- Risk score
- 60/100
- CVSS
- 8.1 v3.1
- Exploit chance (30 days)
- 0.2%
- Published
- 29 Sep 2026
Open in the live forecast Today's forecast
What to know
- What it is
- 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 ce…
- Affected
- jupyterlab (pip) >= 4.6.0, <= 4.6.3; jupyterlab (pip) >= 4.5.0, <= 4.5.10; notebook (pip) >= 7.5.0, <= 7.6.2; jupyterlite (pip) >= 0.7.0, <= 0.8.3
- Fix
- Upgrade jupyterlab to 4.6.4 or 4.5.11; notebook to 7.6.3; jupyterlite to 0.8.4; jupyterlite-core to 0.8.4 (whichever matches your release line) or later.
- Exploitation
- No known exploitation
Story map
At a glance
jupyterlab: Amber, patch this week. 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 ce…
The flaws
- CVE-2026-102831: JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard (CVSS 8.1 · EPSS 0%)
- CVE-2026-102830: JupyterLab: Cross-site scripting (XSS) in JupyterLab via crafted language package (jupyterlab.json) (CVSS 6.8 · EPSS 0%)
The fix
Fix: Upgrade jupyterlab to 4.6.4 or 4.5.11; notebook to 7.6.3; jupyterlite to 0.8.4; jupyterlite-core to 0.8.4 (whichever matches your release line) or later.
Who is exposed: jupyterlab (pip) >= 4.6.0, <= 4.6.3; jupyterlab (pip) >= 4.5.0, <= 4.5.10; notebook (pip) >= 7.5.0, <= 7.6.2; jupyterlite (pip) >= 0.7.0, <= 0.8.3
Where it stands
- No known exploitation
Connects to
- Same weakness: Cross-site scripting (CWE-79). 399 other warnings in 30 days
Why it is Amber
- CVSS 8.1 high
- Remotely exploitable without logging in
- On your watchlist: PyPI
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| jupyterlab | pip | >= 4.6.0, <= 4.6.3 | 4.6.4 |
| jupyterlab | pip | >= 4.5.0, <= 4.5.10 | 4.5.11 |
| notebook | pip | >= 7.5.0, <= 7.6.2 | 7.6.3 |
| jupyterlite | pip | >= 0.7.0, <= 0.8.3 | 0.8.4 |
| jupyterlite-core | pip | >= 0.7.0, <= 0.8.3 | 0.8.4 |
References
- https://github.com/advisories/GHSA-6966-vjj6-99xv
- https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-6966-vjj6-99xv
- https://nvd.nist.gov/vuln/detail/CVE-2026-102831
- https://github.com/jupyterlab/jupyterlab/commit/1a10a7da5ff655849b21581c2633b46483ae0be9
- https://github.com/jupyterlab/jupyterlab/commit/7f9f29e29e0c83fb17b0f11da57d06b3c6a40d96
- https://github.com/jupyterlab/jupyterlab/commit/cf6e89a8d315c4134cefa50c220bca296da466a7
- https://github.com/jupyterlab/jupyterlab/releases/tag/v4.5.11
- https://github.com/jupyterlab/jupyterlab/releases/tag/v4.6.4
- https://github.com/advisories/GHSA-6966-vjj6-99xv
Original description
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.
Last activity 29 Sep 2026. Patch Forecast updates every hour.