CVE-2025-43864: Remix-Run React-Router

High severity, CVSS 7.5. EPSS: 20.5% chance of exploitation in the next 30 days.

React Router is a router for React. Starting in version 7.2.0 and prior to version 7.5.2, it is possible to force an application to switch to SPA mode by adding a header to the request. If the application uses SSR and is forced to switch to SPA, this causes an error that completely corrupts the page. If a cache system is in place, this allows the response containing the error to be cached, resulting in a cache poisoning that strongly impacts the availability of the application. This issue has been patched in version 7.5.2.

Affected products

• Remix-Run React-Router: from 7.2.0, before 7.5.2 (fixed in 7.5.2)

Published 2025-04-25. Last modified 2026-06-17.