CVE-2025-43865: React Router allows pre-render data spoofing on React-Router framework mode
(updated )
After some research, it turns out that it’s possible to modify pre-rendered data by adding a header to the request. This allows to completely spoof its contents and modify all the values of the data object passed to the HTML. Latest versions are impacted.
References
- github.com/advisories/GHSA-cpj6-fhp6-mr6j
- github.com/remix-run/react-router
- github.com/remix-run/react-router/blob/e6c53a0130559b4a9bd47f9cf76ea5b08a69868a/packages/react-router/lib/server-runtime/routes.ts
- github.com/remix-run/react-router/commit/c84302972a152d851cf5dd859ff332b354b70111
- github.com/remix-run/react-router/security/advisories/GHSA-cpj6-fhp6-mr6j
- nvd.nist.gov/vuln/detail/CVE-2025-43865
Code Behaviors & Features
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