Unknown · React Router · CVE-2026-53663
**Name of the Vulnerable Software and Affected Versions**
React Router version 7
**Description**
Insufficient Cross-Site Request Forgery (CSRF) checks in Framework Mode allow bypasses when using 'PUT', 'PATCH', or 'DELETE' requests, as the checks were primarily applied to 'POST' requests. CSRF is a type of attack where an unauthorized command is transmitted from a user that the web application trusts. This issue is mitigated by modern browser protections such as SameSite cookies and CORS preflight checks.
**Recommendations**
Update React Router version 7 to a version containing the fix.
As a temporary mitigation, avoid using Framework Mode or switch to Declarative Mode (`<BrowserRouter>`) or Data Mode (`createBrowserRouter`/`<RouterProvider>`).