{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "versions": [
              {
                "introduced": "0"
              },
              {
                "fixed": "20.8.9"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "68324c21d7b98f53f7bb5a7b3e185bda7106e751"
            }
          ],
          "repo": "https://github.com/capricorn86/happy-dom",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-w4gp-fjgq-3q4g"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-201",
      "CWE-359"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34226.json"
  },
  "details": "Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Versions prior to 20.8.9 may attach cookies from the current page origin (`window.location`) instead of the request target URL when `fetch(..., { credentials: \"include\" })` is used. This can leak cookies from origin A to destination B. Version 20.8.9 fixes the issue.",
  "id": "CVE-2026-34226",
  "modified": "2026-04-01T23:09:09.203934639Z",
  "published": "2026-03-27T21:17:24.777Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34226.json"
    },
    {
      "type": "WEB",
      "url": "https://github.com/capricorn86/happy-dom/blob/f8d8cad41e9722fab9eefb9dfb3cca696462e908/packages/happy-dom/src/fetch/utilities/FetchRequestHeaderUtility.ts"
    },
    {
      "type": "FIX",
      "url": "https://github.com/capricorn86/happy-dom/commit/68324c21d7b98f53f7bb5a7b3e185bda7106e751"
    },
    {
      "type": "FIX",
      "url": "https://github.com/capricorn86/happy-dom/pull/2117"
    },
    {
      "type": "WEB",
      "url": "https://github.com/capricorn86/happy-dom/releases/tag/v20.8.9"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/capricorn86/happy-dom/security/advisories/GHSA-w4gp-fjgq-3q4g"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34226"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Happy DOM's fetch credentials include uses page-origin cookies instead of target-origin cookies"
}