SB2025082136 - Insufficient verification of data authenticity in React Router
Published: August 21, 2025
Security Bulletin ID
SB2025082136
Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Insufficient verification of data authenticity (CVE-ID: CVE-2025-43865)
The vulnerability allows a remote attacker to spoof contents and modify all the values.
The vulnerability exists due to it's possible to modify pre-rendered data by adding a header to the request. A remote attacker can modify pre-rendered data by adding a header to the request to spoof its contents and modify all the values.
Remediation
Install update from vendor's website.
References
- https://github.com/remix-run/react-router/blob/e6c53a0130559b4a9bd47f9cf76ea5b08a69868a/packages/react-router/lib/server-runtime/routes.ts#L87
- https://github.com/remix-run/react-router/commit/c84302972a152d851cf5dd859ff332b354b70111
- https://github.com/remix-run/react-router/security/advisories/GHSA-cpj6-fhp6-mr6j