JupyterLab before 4.5.9 Stored XSS via Extension Manager

{
  "id": "b4f86f234904b1cabb8bd7edbd9c27aa87bebff141ee8a8db10b9feb045e875f",
  "url": "https://osv.dev/vulnerability/BIT-jupyterlab-2026-67338",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "JupyterLab before 4.5.9 Stored XSS via Extension Manager",
    "summary": "JupyterLab before 4.5.9 contains a stored cross-site scripting vulnerability in the Extension Manager that fails to validate URI protocols in package metadata URLs. Attackers can publish malicious PyPI packages with javascript: URLs in project metadata that execute arbitrary JavaScript in the JupyterLab origin when users click the extension name.",
    "evidence": "osv:BIT-jupyterlab-2026-67338",
    "products": [
      {
        "name": {
          "value": "jupyterlab",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "4.5.9",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "BIT-jupyterlab-2026-67338",
      "aliases": [
        "BIT-jupyterlab-2026-67338",
        "CVE-2026-67338",
        "GHSA-vmhf-c436-hxj4"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "4.5.9"
                }
              ]
            }
          ],
          "package": {
            "name": "jupyterlab",
            "purl": "pkg:bitnami/jupyterlab",
            "ecosystem": "Bitnami"
          },
          "severity": [
            {
              "type": "CVSS_V4",
              "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
            }
          ],
          "database_specific": {
            "source": "https://github.com/bitnami/vulndb/tree/main/data/jupyterlab/BIT-jupyterlab-2026-67338.json"
          }
        }
      ],
      "modified": "2026-10-14T11:11:02.670615521Z",
      "provider": "osv",
      "references": [
        "https://github.com/jupyterlab/jupyterlab/commit/4e61e07d0a91145b53fbf96ac74b0387f6bc51f6",
        "https://github.com/jupyterlab/jupyterlab/commit/d5d961f6e10a6442dddbf94d9a976b3897055a12",
        "https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-vmhf-c436-hxj4",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-67338",
        "https://www.vulncheck.com/advisories/jupyterlab-before-stored-xss-via-extension-manager"
      ],
      "provider_metadata": {
        "cpes": [
          "cpe:2.3:a:jupyter:jupyterlab:*:*:*:*:*:python:*:*"
        ],
        "severity": "Medium"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-67338",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 316245,
  "published_at": "2026-10-14T08:45:27.772+00:00"
}