{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-40171",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-40171",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-05-06T19:36:32.072Z",
    "updatedAt": "2026-05-08T03:55:41.465Z",
    "importedAt": "2026-10-24T01:58:08.712Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "Jupyter Notebook and JupyterLab token theft via stored XSS in help command linker",
      "summary": "In Jupyter Notebook versions 7.0.0 through 7.5.5, JupyterLab versions 4.5.6 and earlier, and the corresponding @jupyter-notebook/help-extension and @jupyterlab/help-extension packages before 7.5.6 and 4.5.7, a stored cross-site scripting issue in the help command linker can be chained with attacker-controlled notebook content to steal authentication tokens with a single click.\n\nAn attacker can craft a malicious notebook file containing elements that appear indistinguishable from legitimate controls and trigger execution when a user interacts with them. Successful exploitation allows theft of the user's authentication token and complete takeover of the Jupyter session through the REST API, including reading files, creating or modifying files, accessing kernels to execute arbitrary code, and creating terminals for shell access. This issue has been fixed in Notebook 7.5.6, JupyterLab 4.5.7, @jupyter-notebook/help-extension 7.5.6, and @jupyterlab/help-extension 4.5.7. As a workaround, disable the affected help extensions or set allowCommandLinker to false in the sanitizer configuration.",
      "affected": [
        {
          "vendor": "jupyter",
          "product": "notebook",
          "versions": [
            {
              "version": ">=7.0.0, <= 7.5.5",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "jupyterlab",
          "product": "help-extension",
          "versions": [
            {
              "version": "<=4.5.6",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "jupyterlab",
          "product": "jupyterlab",
          "versions": [
            {
              "version": "<= 4.5.6",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "jupyter-notebook",
          "product": "help-extension",
          "versions": [
            {
              "version": ">=7.0.0,<= 7.5.5",
              "status": "affected"
            }
          ]
        }
      ]
    }
  }
}