{
  "canonical_id": "nextjs--CVE-2025-30218",
  "system_id": "nextjs",
  "display_name": "Next.js",
  "category": "frameworks",
  "advisory_mode": "core",
  "title": "Next.js may leak x-middleware-subrequest-id to external hosts",
  "summary": "## Summary\nIn the process of remediating [CVE-2025-29927](https://github.com/advisories/GHSA-f82v-jwr5-mffw), we looked at other possible exploits of Middleware. We independently verified this low severity vulnerability in parallel with two reports from independent researchers.\n\nLearn more [here](https://vercel.com/changelog/cve-2025-30218-5DREmEH765PoeAsrNNQj3O).\n\n## Credit\n\nThank you to Jinseo Kim [kjsman](https://hackerone.com/kjsman?type=user) and\u00a0[RyotaK](https://hackerone.com/ryotak?type=user) (GMO Flatt Security Inc.) with [takumi-san.ai](https://takumi-san.ai)\u00a0for the responsible disclosure. These researchers were awarded as part of our bug bounty program.",
  "published_at": "2025-04-02T22:35:37Z",
  "updated_at": "2025-10-13T15:35:50Z",
  "severity": "medium",
  "cvss_score": 4.0,
  "exploit_status": "unknown",
  "source_confidence": "official",
  "official_source_url": "https://github.com/vercel/next.js/security/advisories/GHSA-223j-4rm8-mrmf",
  "secondary_source_urls": [
    "https://nvd.nist.gov/vuln/detail/CVE-2025-30218",
    "https://github.com/vercel/next.js",
    "https://vercel.com/changelog/cve-2025-30218-5DREmEH765PoeAsrNNQj3O"
  ],
  "aliases": [
    "CVE-2025-30218",
    "GHSA-223j-4rm8-mrmf"
  ],
  "cve_ids": [
    "CVE-2025-30218"
  ],
  "ghsa_ids": [
    "GHSA-223j-4rm8-mrmf"
  ],
  "osv_ids": [
    "GHSA-223j-4rm8-mrmf"
  ],
  "affected_versions": [
    "12.3.5",
    "13.5.9",
    "14.2.25",
    "15.2.3",
    "introduced=12.3.5, fixed<12.3.6",
    "introduced=13.5.9, fixed<13.5.10",
    "introduced=14.2.25, fixed<14.2.26",
    "introduced=15.2.3, fixed<15.2.4"
  ],
  "fixed_versions": [
    "12.3.6",
    "13.5.10",
    "14.2.26",
    "15.2.4"
  ],
  "package_name": "next",
  "render_markdown": true,
  "case_path": "07-framework-security/frameworks/nextjs/cases/nextjs-cve-2025-30218.md",
  "secure_code_topics": [
    "authz-server-side-recheck",
    "proxy-trust-boundary",
    "token-cookie-storage"
  ],
  "status": "generated",
  "triage_reasons": [],
  "metadata": {
    "source_names": [
      "OSV Next.js"
    ],
    "source_kinds": [
      "osv-batch"
    ],
    "candidate_count": 1
  }
}