HighFix available

JupyterLab: Cross-site scripting (XSS) in JupyterLab via notebook cells pasted from the system clipboard

Type: advisorySource: OSV1 source record

## Description JupyterLab 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 `" } } ] } ] ``` Users are affected if all of the following are true: - they run JupyterLab 4.5.0 through 4.6.3, or an application that bundles it such as Notebook 7.5+; - 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 - they run a Paste Cells command (e.g. from context menu, command palette, shortcut) while attacker-controlled text is in the clipboard; and - `pasteCodeCellsWithoutOutput` is off, the default, so the pasted cell keeps its outputs ### Impact The 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. Only 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. The attacker needs no JupyterLab account and no access to th

Announced 1 Oct 2026Group revision 2

Original source ↗

Updated source: PYSEC-2026-4060. See its source record below.

GHSA-6966-vjj6-99xv

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: osv:GHSA-6966-vjj6-99xv

jupyterlab

Source reference: /affected/0/package/name

Affected versions: 4.6.0
Source reference: /affected/0/versions
4.6.1
Source reference: /affected/0/versions
4.6.2
Source reference: /affected/0/versions
4.6.3
Source reference: /affected/0/versions
Fixed versions: 4.6.4
Source reference: /affected/0/ranges
Prerequisites: Not stated in this record

jupyterlab

Source reference: /affected/1/package/name

Affected versions: 4.5.0
Source reference: /affected/1/versions
4.5.1
Source reference: /affected/1/versions
4.5.10
Source reference: /affected/1/versions
4.5.2
Source reference: /affected/1/versions
4.5.3
Source reference: /affected/1/versions
4.5.4
Source reference: /affected/1/versions
4.5.5
Source reference: /affected/1/versions
4.5.6
Source reference: /affected/1/versions
4.5.7
Source reference: /affected/1/versions
4.5.8
Source reference: /affected/1/versions
4.5.9
Source reference: /affected/1/versions
Fixed versions: 4.5.11
Source reference: /affected/1/ranges
Prerequisites: Not stated in this record

notebook

Source reference: /affected/2/package/name

Affected versions: 7.5.0
Source reference: /affected/2/versions
7.5.1
Source reference: /affected/2/versions
7.5.2
Source reference: /affected/2/versions
7.5.3
Source reference: /affected/2/versions
7.5.4
Source reference: /affected/2/versions
7.5.5
Source reference: /affected/2/versions
7.5.6
Source reference: /affected/2/versions
7.5.7
Source reference: /affected/2/versions
7.6.0
Source reference: /affected/2/versions
7.6.0a0
Source reference: /affected/2/versions
7.6.0a1
Source reference: /affected/2/versions
7.6.0a2
Source reference: /affected/2/versions
7.6.0a3
Source reference: /affected/2/versions
7.6.0a4
Source reference: /affected/2/versions
7.6.0a5
Source reference: /affected/2/versions
7.6.0b0
Source reference: /affected/2/versions
7.6.0b1
Source reference: /affected/2/versions
7.6.0rc0
Source reference: /affected/2/versions
7.6.0rc1
Source reference: /affected/2/versions
7.6.1
Source reference: /affected/2/versions
7.6.2
Source reference: /affected/2/versions
Fixed versions: 7.6.3
Source reference: /affected/2/ranges
Prerequisites: Not stated in this record

jupyterlite

Source reference: /affected/3/package/name

Affected versions: 0.7.0
Source reference: /affected/3/versions
0.7.1
Source reference: /affected/3/versions
0.7.2
Source reference: /affected/3/versions
0.7.3
Source reference: /affected/3/versions
0.7.4
Source reference: /affected/3/versions
0.7.5
Source reference: /affected/3/versions
0.7.6
Source reference: /affected/3/versions
0.8.0
Source reference: /affected/3/versions
0.8.0a0
Source reference: /affected/3/versions
0.8.0a1
Source reference: /affected/3/versions
0.8.0a2
Source reference: /affected/3/versions
0.8.0b0
Source reference: /affected/3/versions
0.8.0b1
Source reference: /affected/3/versions
0.8.0rc0
Source reference: /affected/3/versions
0.8.1
Source reference: /affected/3/versions
0.8.2
Source reference: /affected/3/versions
0.8.3
Source reference: /affected/3/versions
Fixed versions: 0.8.4
Source reference: /affected/3/ranges
Prerequisites: Not stated in this record

jupyterlite-core

Source reference: /affected/4/package/name

Affected versions: 0.7.0
Source reference: /affected/4/versions
0.7.1
Source reference: /affected/4/versions
0.7.2
Source reference: /affected/4/versions
0.7.3
Source reference: /affected/4/versions
0.7.4
Source reference: /affected/4/versions
0.7.5
Source reference: /affected/4/versions
0.7.6
Source reference: /affected/4/versions
0.8.0
Source reference: /affected/4/versions
0.8.0a0
Source reference: /affected/4/versions
0.8.0a1
Source reference: /affected/4/versions
0.8.0a2
Source reference: /affected/4/versions
0.8.0b0
Source reference: /affected/4/versions
0.8.0b1
Source reference: /affected/4/versions
0.8.0rc0
Source reference: /affected/4/versions
0.8.1
Source reference: /affected/4/versions
0.8.2
Source reference: /affected/4/versions
0.8.3
Source reference: /affected/4/versions
Fixed versions: 0.8.4
Source reference: /affected/4/ranges
Prerequisites: Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "4.6.0"
          },
          {
            "fixed": "4.6.4"
          }
        ]
      }
    ],
    "package": {
      "name": "jupyterlab",
      "purl": "pkg:pypi/jupyterlab",
      "ecosystem": "PyPI"
    },
    "versions": [
      "4.6.0",
      "4.6.1",
      "4.6.2",
      "4.6.3"
    ],
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-6966-vjj6-99xv/GHSA-6966-vjj6-99xv.json",
      "last_known_affected_version_range": "<= 4.6.3"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "4.5.0"
          },
          {
            "fixed": "4.5.11"
          }
        ]
      }
    ],
    "package": {
      "name": "jupyterlab",
      "purl": "pkg:pypi/jupyterlab",
      "ecosystem": "PyPI"
    },
    "versions": [
      "4.5.0",
      "4.5.1",
      "4.5.10",
      "4.5.2",
      "4.5.3",
      "4.5.4",
      "4.5.5",
      "4.5.6",
      "4.5.7",
      "4.5.8",
      "4.5.9"
    ],
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-6966-vjj6-99xv/GHSA-6966-vjj6-99xv.json",
      "last_known_affected_version_range": "<= 4.5.10"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "7.5.0"
          },
          {
            "fixed": "7.6.3"
          }
        ]
      }
    ],
    "package": {
      "name": "notebook",
      "purl": "pkg:pypi/notebook",
      "ecosystem": "PyPI"
    },
    "versions": [
      "7.5.0",
      "7.5.1",
      "7.5.2",
      "7.5.3",
      "7.5.4",
      "7.5.5",
      "7.5.6",
      "7.5.7",
      "7.6.0",
      "7.6.0a0",
      "7.6.0a1",
      "7.6.0a2",
      "7.6.0a3",
      "7.6.0a4",
      "7.6.0a5",
      "7.6.0b0",
      "7.6.0b1",
      "7.6.0rc0",
      "7.6.0rc1",
      "7.6.1",
      "7.6.2"
    ],
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-6966-vjj6-99xv/GHSA-6966-vjj6-99xv.json",
      "last_known_affected_version_range": "<= 7.6.2"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0.7.0"
          },
          {
            "fixed": "0.8.4"
          }
        ]
      }
    ],
    "package": {
      "name": "jupyterlite",
      "purl": "pkg:pypi/jupyterlite",
      "ecosystem": "PyPI"
    },
    "versions": [
      "0.7.0",
      "0.7.1",
      "0.7.2",
      "0.7.3",
      "0.7.4",
      "0.7.5",
      "0.7.6",
      "0.8.0",
      "0.8.0a0",
      "0.8.0a1",
      "0.8.0a2",
      "0.8.0b0",
      "0.8.0b1",
      "0.8.0rc0",
      "0.8.1",
      "0.8.2",
      "0.8.3"
    ],
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-6966-vjj6-99xv/GHSA-6966-vjj6-99xv.json",
      "last_known_affected_version_range": "<= 0.8.3"
    }
  },
  {
    "ranges": [
      {
        "type": "ECOSYSTEM",
        "events": [
          {
            "introduced": "0.7.0"
          },
          {
            "fixed": "0.8.4"
          }
        ]
      }
    ],
    "package": {
      "name": "jupyterlite-core",
      "purl": "pkg:pypi/jupyterlite-core",
      "ecosystem": "PyPI"
    },
    "versions": [
      "0.7.0",
      "0.7.1",
      "0.7.2",
      "0.7.3",
      "0.7.4",
      "0.7.5",
      "0.7.6",
      "0.8.0",
      "0.8.0a0",
      "0.8.0a1",
      "0.8.0a2",
      "0.8.0b0",
      "0.8.0b1",
      "0.8.0rc0",
      "0.8.1",
      "0.8.2",
      "0.8.3"
    ],
    "database_specific": {
      "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-6966-vjj6-99xv/GHSA-6966-vjj6-99xv.json",
      "last_known_affected_version_range": "<= 0.8.3"
    }
  }
]

Related CVEs: CVE-2026-102831
Source reference: /aliases

Publisher severity

high

Source reference: /database_specific/severity

Linked CVE context

These ratings describe the referenced vulnerabilities and products. They are not a severity rating for every application using this dependency.

CVE-2026-102831 · High

jupyterlab, notebook, jupyterlite-core

Event: #62589 · Revision 1
Added to Heist Feed: Sun, 25 Oct 2026 19:29:28 GMT
Publisher date: Thu, 01 Oct 2026 15:20:41 GMT

Read the original announcement

Revision history

25 Oct 2026GHSA-6966-vjj6-99xv · Revision 1Source updated