Vulnerabilities in pkg:pypi/jupyterlite
PACKAGECVE-2026-102831 is a HIGH (CVSS 8.1) cross-site scripting vulnerability (CWE-345: Insufficient Verification of Data Authenticity) affecting JupyterLab libraries in the PyPI ecosystem. The issue involves cross-site scripting (xss) in jupyterlab via notebook cells pasted from the system clipboard. Remediation is available by upgrading affected packages to version 4.6.4, 4.5.11, 7.6.3, 0.8.4.
pkg:pypi/jupyterlite
Vulnerability advisories affecting package pkg:pypi/jupyterlite. Select an advisory below to view technical details or fixes.
| Advisory ID | CVE / NVD | Severity | Summary |
|---|---|---|---|
| GHSA-6966-vjj6-99xv | CVE-2026-102831 | HIGH | JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard |
CVE-2026-102831 at a Glance
Security Impact
CVSS: 8.1
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N).
How to Fix CVE-2026-102831
To remediate this vulnerability, upgrade all affected JupyterLab dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
pip install jupyterlab>=4.6.4
pip install jupyterlab>=4.5.11
pip install notebook>=7.6.3
pip install jupyterlite>=0.8.4
pip install jupyterlite-core>=0.8.4
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
pip show jupyterlab
How to Check if You Are Affected
To determine whether your Python environment is affected by CVE-2026-102831, inspect your installed packages using pip:
pip show jupyterlab
Analyze the terminal output to locate any version of JupyterLab in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.6.4), your application is affected.
Note: The pip show jupyterlab command checks currently installed packages in your active Python environment.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-345: Insufficient Verification of Data Authenticity, where the product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data. In JupyterLab, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-102831 Affected JupyterLab Versions
5 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
jupyterlab
|
PyPI |
≥ 4.6.0
< 4.6.4
|
4.6.4
|
|
jupyterlab
|
PyPI |
≥ 4.5.0
< 4.5.11
|
4.5.11
|
|
notebook
|
PyPI |
≥ 7.5.0
< 7.6.3
|
7.6.3
|
|
jupyterlite
|
PyPI |
≥ 0.7.0
< 0.8.4
|
0.8.4
|
|
jupyterlite-core
|
PyPI |
≥ 0.7.0
< 0.8.4
|
0.8.4
|
References
Frequently Asked Questions
What is CVE-2026-102831?
Which JupyterLab versions are affected?
What version fixes CVE-2026-102831?
Is jupyterlab affected?
Is notebook affected?
What is the CVSS score of CVE-2026-102831?
What CWE is associated with CVE-2026-102831?
How can I check PyPI dependencies for CVE-2026-102831?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-6966-vjj6-99xv",
"modified" : "2026-10-01T15:20:41Z",
"published" : "2026-10-01T15:20:41Z",
"aliases" : [ "CVE-2026-102831" ],
"summary" : "JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard",
"details" : "## Description\n\nJupyterLab 4.5.0 enabled copying and pasing cells through the system clipboard. The paste path parses clipboard text as cell JSON and inserts the cells without clearing `metadata.trusted`, so a payload can declare its own output as trusted. JupyterLab does not sanitize a trusted output and evaluates the `<script>` elements it contains, so pasting the cell runs attacker's JavaScript in the JupyterLab origin. The same payload with `\"trusted\": false` is sanitized.\n\n```json\n[\n {\n \"cell_type\": \"code\",\n \"execution_count\": null,\n \"source\": \"\",\n \"metadata\": { \"trusted\": true },\n \"outputs\": [\n {\n \"output_type\": \"display_data\",\n \"metadata\": {},\n \"data\": { \"text/html\": \"<script>/* runs on paste */</script>\" }\n }\n ]\n }\n]\n```\n\nUsers are affected if all of the following are true:\n\n- they run JupyterLab 4.5.0 through 4.6.3, or an application that bundles it such as Notebook 7.5+;\n- if running 4.5.2 or newer, `useSystemClipboardForCells` is enabled - it is off by default in 4.5.2+, and always enabled on 4.5.0 and 4.5.1 with no opt-out\n- they run a Paste Cells command (e.g. from context menu, command palette, shortcut) while attacker-controlled text is in the clipboard; and\n- `pasteCodeCellsWithoutOutput` is off, the default, so the pasted cell keeps its outputs\n\n\n### Impact\n\nThe script runs in the JupyterLab page, in the same origin and session as the authenticated user, so it can call the Jupyter Server REST API as that user: read and write any file under the server root, start a kernel and run code in it, and open a terminal where terminals are enabled. It runs on paste, without the user executing anything.\n\nOnly the output of a code cell can run a script this way. Markdown and raw cells are always sanitized, as the [trust documentation](https://jupyterlab.readthedocs.io/en/latest/user/notebook.html#trust) states.\n\nThe attacker needs no JupyterLab account and no access to the server, only the user's clipboard at the moment of the paste. A web page can replace the text you copy from it, or write the clipboard directly once you have given it permission. Both need you to click or press a key on that page first.\n\n### Patches\n\nJupyterLab [`v4.6.4`](https://github.com/jupyterlab/jupyterlab/releases/tag/v4.6.4) and [`v4.5.11`](https://github.com/jupyterlab/jupyterlab/releases/tag/v4.5.11) contain the patch. Cells read from the system clipboard that cannot be traced to the current window no longer carry `metadata.trusted` into the notebook, so their outputs are sanitized like any other content of unknown origin.\n\nUsers of applications that depend on JupyterLab, such as Notebook v7+, should update `jupyterlab` package too.\n\n### Workarounds\n\nOn 4.5.2 and later, confirm that the system clipboard is not in use for cells. The setting is off by default; check Settings, Notebook, or the raw value:\n\n```json\n{\n \"@jupyterlab/notebook-extension:tracker\": {\n \"useSystemClipboardForCells\": false\n }\n}\n```\n\nWith that setting off, cell copy and paste use JupyterLab's in-application clipboard, which never leaves the page. The cost is that cells can no longer be copied between browser tabs or windows.\n\nOn 4.5.0 and 4.5.1 there is no such setting, and every paste reads the system clipboard and upgrade is highly recommended.\n\nPasting cells without their outputs also stops the script from running, at the cost of discarding outputs on every paste:\n\n```json\n{\n \"@jupyterlab/notebook-extension:tracker\": {\n \"pasteCodeCellsWithoutOutput\": true\n }\n}\n```",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "PyPI",
"name" : "jupyterlab"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.6.0"
}, {
"fixed" : "4.6.4"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 4.6.3"
}
}, {
"package" : {
"ecosystem" : "PyPI",
"name" : "jupyterlab"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.5.0"
}, {
"fixed" : "4.5.11"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 4.5.10"
}
}, {
"package" : {
"ecosystem" : "PyPI",
"name" : "notebook"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "7.5.0"
}, {
"fixed" : "7.6.3"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 7.6.2"
}
}, {
"package" : {
"ecosystem" : "PyPI",
"name" : "jupyterlite"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0.7.0"
}, {
"fixed" : "0.8.4"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 0.8.3"
}
}, {
"package" : {
"ecosystem" : "PyPI",
"name" : "jupyterlite-core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0.7.0"
}, {
"fixed" : "0.8.4"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 0.8.3"
}
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-6966-vjj6-99xv"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-102831"
}, {
"type" : "WEB",
"url" : "https://github.com/jupyterlab/jupyterlab/commit/1a10a7da5ff655849b21581c2633b46483ae0be9"
}, {
"type" : "WEB",
"url" : "https://github.com/jupyterlab/jupyterlab/commit/7f9f29e29e0c83fb17b0f11da57d06b3c6a40d96"
}, {
"type" : "WEB",
"url" : "https://github.com/jupyterlab/jupyterlab/commit/cf6e89a8d315c4134cefa50c220bca296da466a7"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/jupyterlab/jupyterlab"
}, {
"type" : "WEB",
"url" : "https://github.com/jupyterlab/jupyterlab/releases/tag/v4.5.11"
}, {
"type" : "WEB",
"url" : "https://github.com/jupyterlab/jupyterlab/releases/tag/v4.6.4"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-345", "CWE-79" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2026-10-01T15:20:41Z",
"nvd_published_at" : "2026-09-29T19:17:25Z"
}
}