{
  "cveId": "CVE-2026-42557",
  "url": "https://patchblox.com/security/cve/CVE-2026-42557",
  "summary": "CVE-2026-42557 is fixed in jupyterlab on 1 platform by DEBIAN-CVE-2026-42557 (version 4.4.10\u002Bds1\u002B~3.1.0\u002B~0.16.6\u002B~cs1.4.4-3), released May 13, 2026. It is not reported as exploited. Patch Radar priority: Urgent.",
  "title": "jupyterlab: jupyterlab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Arc...",
  "description": "jupyterlab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. Prior to 4.5.7, JupyterLab\u0027s HTML sanitizer allowlists data-commandlinker-command and data-commandlinker-args on button elements, while CommandLinker listens for all click events on document.body and executes the named command without checking whether the element came from trusted JupyterLab UI. A notebook with a pre-saved HTML cell output containing a deceptive button can trigger arbitrary JupyterLab commands - including arbitrary code execution - on a single user click, without any code being submitted for execution by the user. This vulnerability is fixed in 4.5.7.",
  "published": "2026-05-13T16:16:48Z",
  "severity": "critical",
  "cvss": 9.6,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
  "epss": 0.00486,
  "epssPercentile": 0.42159,
  "priority": "Urgent",
  "priorityTier": 2,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "jupyterlab",
      "release": "Debian 14",
      "fixedVersion": "4.4.10\u002Bds1\u002B~3.1.0\u002B~0.16.6\u002B~cs1.4.4-3",
      "fix": "DEBIAN-CVE-2026-42557",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-42557",
      "released": "2026-05-13T16:16:48Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}