{"id":"CVE-2026-53667","aliases":["GHSA-h8fp-f39c-q6mh"],"url":"https://o3.security/vulnerability/CVE-2026-53667","summary":"React Router: Cross-site Scripting is Possible due to Missing RSCErrorHandler Protocol Validation (Incomplete fix for CVE-2026-53667)","details":"This is a follow up to https://github.com/remix-run/react-router/security/advisories/GHSA-8646-j5j9-6r62.  React Router was alerted of a code path in the (unstable) RSC error handling path in which redirects from untrusted sources could still result in an XSS vector via attacker-supplied redirect targets\n\n> [!NOTE]\n> This only affects your application if you are using the unstable RSC APIs","published":"2026-07-27T21:21:16.084Z","modified":"2026-10-21T02:30:18.633863356Z","cvss":{"score":6.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N"},"epss":{"score":0.00203,"percentile":0.10355,"asOf":"2026-09-13"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"react-router","fixedVersion":"7.18.0"}],"fix":{"url":"https://github.com/remix-run/react-router/commit/ce596e823f0d7b883a433af1d5a839a8b9fe0242","label":"remix-run/react-router@ce596e8"},"references":[{"type":"WEB","url":"https://github.com/remix-run/react-router/blob/main/CHANGELOG.md#v7180"},{"type":"WEB","url":"https://github.com/remix-run/react-router/releases/tag/react-router@7.18.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53667.json"},{"type":"ADVISORY","url":"https://github.com/remix-run/react-router/security/advisories/GHSA-h8fp-f39c-q6mh"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53667"},{"type":"FIX","url":"https://github.com/remix-run/react-router/commit/ce596e823f0d7b883a433af1d5a839a8b9fe0242"},{"type":"FIX","url":"https://github.com/remix-run/react-router/pull/15177"},{"type":"PACKAGE","url":"https://github.com/remix-run/react-router"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T02:30:18.633863356Z"}}