JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard
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.
CVE-2026-102831
Primary source · Revision 2
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-102831
jupyterlab
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
notebook
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
jupyterlite-core
Source reference: /containers/cna/affected/2/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "jupyterlab",
"product": "jupyterlab",
"versions": [
{
"status": "affected",
"version": ">= 4.5.0, < 4.5.11"
},
{
"status": "affected",
"version": ">= 4.6.0, < 4.6.4"
}
]
},
{
"vendor": "jupyterlab",
"product": "notebook",
"versions": [
{
"status": "affected",
"version": ">= 7.5.0, < 7.6.3"
}
]
},
{
"vendor": "jupyterlab",
"product": "jupyterlite-core",
"versions": [
{
"status": "affected",
"version": ">= 0.7.0, < 0.8.4"
}
]
}
]- Related CVEs
- CVE-2026-102831
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #62590 · Revision 2
- Added to Heist Feed
- Publisher date