Answer in brief
CVE-2026-102831 records a High severity (CVSS 8.1) vulnerability in JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard. The current sources do not mark it as known exploited. The current feed maps jupyterlab/jupyterlab (generic), jupyterlab/jupyterlite-core (generic), jupyterlab/notebook (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps jupyterlab/jupyterlab (generic), jupyterlab/jupyterlite-core (generic), jupyterlab/notebook (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| jupyterlab/jupyterlabgeneric | >=4.5.0 <4.5.11 || >=4.6.0 <4.6.4 | 4.5.11, 4.6.4 |
| jupyterlab/jupyterlite-coregeneric | >=0.7.0 <0.8.4 | 0.8.4 |
| jupyterlab/notebookgeneric | >=7.5.0 <7.6.3 | 7.6.3 |
Published upstream
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 29, 2026
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.
Quoted source text, attributed separately from HOL analysis.