~ / search / GHSA-337j-9hxr-rhxg

GHSA-337j-9hxr-rhxg

React Router: Arbitrary Constructor Injection via deserializeErrors() in React Router SSR Hydration

Source: GitHub Advisory Database (reviewed) Moderate CVE-2026-53666

Packages

EcosystemPackageAffectedFixed in
npm react-router >= 6.4.0, < 7.18.0 7.18.0

Details

As written in the advisory (Markdown source, shown as plain text).

If application code allows attacker supplied input to overwrite certain aspects of errors caught by the SSR process, then it was possible for attacker to trigger unexpected constructor execution on the client which would trigger outbound network traffic. This is only possible with very specific (and unlikely) application layer code. > [!NOTE] > This does not impact your application if you are using Declarative Mode. This only impacts Framework Mode and Data Mode applications doing manual SSR/hydration

References

External links from the advisory. They lead to third-party sites.