GitHub Advisoryadvisory · npm
GHSA-f22v-gfqf-p8f3 React Router has stored XSS via unescaped Location header in prerendered redirect HTML
MEDIUM
Official page ↗
- Aliases
- CVE-2026-33244
- Ecosystem
- npm
- Packages
- react-router
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- Weaknesses
- CWE-79
- Reviewed
- 2026-06-03
Affected packages
• npm react-router: >= 7.5.1, < 7.13.2 → fixed in 7.13.2
Description
When using React Router v7 Framework Mode with Pre-rendering enabled, an improper neutralization of the HTTP `Location` header value can permit Cross-Site Scripting (XSS) in statically generated HTML files if the redirect location comes from an untrusted source.
> [!NOTE]
> This does not impact your React Router application if you are using Declarative Mode (``) or Data Mode (`createBrowserRouter`/``).
Related
Alias · CVE (1)
- CVE-2026-33244 React Router is a router for React. vulnerability
Weakness · CWE (1)
- CWE-79 Improper Neutralization of Input During Web Page Generation weakness
References
- https://github.com/remix-run/react-router/security/advisories/GHSA-f22v-gfqf-p8f3 web
- https://nvd.nist.gov/vuln/detail/CVE-2026-33244 advisory
- https://github.com/remix-run/react-router/pull/14880 web
- https://github.com/remix-run/react-router/commit/ea28e66926460656815cee9b7f2dfaa872513a8c web
- https://github.com/remix-run/react-router package
- https://github.com/remix-run/react-router/blob/react-router%407.13.2/CHANGELOG.md#v7132 web