MediumGHSA-h8fp-f39c-q6mhCVE-2026-53667

React Router: RSCErrorHandler Missing Protocol Validation (XSS)

Published 23 Jul 2026 · Updated 10 Sept 2026

Affected package

react-routernpm
Affected
>=7.11.0 <7.18.0
Fixed in
7.18.0
Update to the fixed version for your release line, for example:npm install react-router@7.18.0

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

> [!NOTE] > This only affects your application if you are using the unstable RSC APIs

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References

Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.