{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "express"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.22.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "express"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.0.0"
            },
            {
              "fixed": "5.2.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-51999"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-915"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-12-01T18:59:17Z",
    "nvd_published_at": "2025-12-01T21:15:49Z",
    "severity": "LOW"
  },
  "details": "## Withdrawn Advisory\nThis advisory has been withdrawn because it describes a correctness bug, not a vulnerability with real security impact. This link is maintained to preserve external references.\n\n## Original Description\n### Impact\n\nwhen using the extended query parser in express (`\u0027query parser\u0027: \u0027extended\u0027`), the `request.query` object inherits all object prototype properties, but these properties can be overwritten by query string parameter keys that match the property names\n\n\u003e [!IMPORTANT]  \n\u003e the extended query parser is the default in express 4; this was changed in express 5 which by default uses the simple query parser\n\n### Patches\n\nthe issue has been patched to ensure `request.query` is a plain object so `request.query` no longer has object prototype properties. this brings the default behavior of extended query parsing in line with express\u0027s default simple query parser\n\n### Workaround\n\nthis only impacts users using extended query parsing (`\u0027query parser\u0027: \u0027extended\u0027`), which is the default in express 4, but not express 5.  all users are encouraged to upgrade to the patched versions, but can otherwise work around this issue:\n\n#### provide `qs` directly and specify `plainObjects: true`\n\n```js\napp.set(\u0027query parser\u0027,\n  function (str) {\n    return qs.parse(str, {\n      plainObjects: true\n  });\n});\n```",
  "id": "GHSA-pj86-cfqh-vqx6",
  "modified": "2025-12-02T15:11:19Z",
  "published": "2025-12-01T18:59:17Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/expressjs/express/security/advisories/GHSA-pj86-cfqh-vqx6"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-51999"
    },
    {
      "type": "WEB",
      "url": "https://github.com/expressjs/express/commit/2f64f68c37c64ae333e41ff38032d21860f22255"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/expressjs/express"
    },
    {
      "type": "WEB",
      "url": "https://github.com/expressjs/express/releases/tag/4.22.0"
    },
    {
      "type": "WEB",
      "url": "https://github.com/expressjs/express/releases/tag/v5.2.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Withdrawn Advisory: express improperly controls modification of query properties",
  "withdrawn": "2025-12-02T15:11:19Z"
}