{"id":"CVE-2025-31137","aliases":["GHSA-4q56-crqp-v477"],"url":"https://o3.security/vulnerability/CVE-2025-31137","summary":"Remix and React Router allow URL manipulation via Host / X-Forwarded-Host headers","details":"React Router is a multi-strategy router for React bridging the gap from React 18 to React 19. There is a vulnerability in Remix/React Router that affects all Remix 2 and React Router 7 consumers using the Express adapter. Basically, this vulnerability allows anyone to spoof the URL used in an incoming Request by putting a URL pathname in the port section of a URL that is part of a Host or X-Forwarded-Host header sent to a Remix/React Router request handler. This issue has been patched and released in Remix 2.16.3 and React Router 7.4.1.","published":"2025-04-01T18:20:32.660Z","modified":"2026-08-12T03:51:19.027421204Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"@react-router/express","fixedVersion":"7.4.1"},{"ecosystem":"npm","name":"@remix-run/express","fixedVersion":"2.16.3"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/31xxx/CVE-2025-31137.json"},{"type":"ADVISORY","url":"https://github.com/remix-run/react-router/security/advisories/GHSA-4q56-crqp-v477"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-31137"},{"type":"PACKAGE","url":"https://github.com/remix-run/react-router"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:19.027421204Z"}}