{"id":"GHSA-223j-4rm8-mrmf","summary":"Next.js may leak x-middleware-subrequest-id to external hosts","details":"## 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 [RyotaK](https://hackerone.com/ryotak?type=user) (GMO Flatt Security Inc.) with [takumi-san.ai](https://takumi-san.ai) for the responsible disclosure. These researchers were awarded as part of our bug bounty program.","aliases":["CVE-2025-30218"],"modified":"2025-10-13T15:35:50Z","published":"2025-04-02T22:35:37Z","database_specific":{"github_reviewed_at":"2025-04-02T22:35:37Z","nvd_published_at":"2025-04-02T22:15:19Z","cwe_ids":["CWE-200"],"severity":"LOW","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/vercel/next.js/security/advisories/GHSA-223j-4rm8-mrmf"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-30218"},{"type":"PACKAGE","url":"https://github.com/vercel/next.js"},{"type":"WEB","url":"https://vercel.com/changelog/cve-2025-30218-5DREmEH765PoeAsrNNQj3O"}],"affected":[{"package":{"name":"next","ecosystem":"npm","purl":"pkg:npm/next"},"ranges":[{"type":"SEMVER","events":[{"introduced":"12.3.5"},{"fixed":"12.3.6"}]}],"versions":["12.3.5"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/04/GHSA-223j-4rm8-mrmf/GHSA-223j-4rm8-mrmf.json"}},{"package":{"name":"next","ecosystem":"npm","purl":"pkg:npm/next"},"ranges":[{"type":"SEMVER","events":[{"introduced":"13.5.9"},{"fixed":"13.5.10"}]}],"versions":["13.5.9"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/04/GHSA-223j-4rm8-mrmf/GHSA-223j-4rm8-mrmf.json"}},{"package":{"name":"next","ecosystem":"npm","purl":"pkg:npm/next"},"ranges":[{"type":"SEMVER","events":[{"introduced":"14.2.25"},{"fixed":"14.2.26"}]}],"versions":["14.2.25"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/04/GHSA-223j-4rm8-mrmf/GHSA-223j-4rm8-mrmf.json"}},{"package":{"name":"next","ecosystem":"npm","purl":"pkg:npm/next"},"ranges":[{"type":"SEMVER","events":[{"introduced":"15.2.3"},{"fixed":"15.2.4"}]}],"versions":["15.2.3"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/04/GHSA-223j-4rm8-mrmf/GHSA-223j-4rm8-mrmf.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U"}]}