React Router: RSCErrorHandler Missing Protocol Validation (XSS)

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...

EUVD-2026-33988

React Router vulnerable to XSS in unstable RSC redirect handling via javascript: redirect targets...