High severity · published Apr 25, 2025
CVE-2025-43865
React Router allows pre-render data spoofing on React-Router framework mode
8.2
CVSS
0.8%
EPSS
No
On KEV
Description
React Router is a router for React. In versions on the 7.0 branch prior to version 7.5.2, 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. This issue has been patched in version 7.5.2.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 57% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RE
react-router · remix-run
>= 7.0, < 7.5.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-43865
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-43865
github.com
https://github.com/remix-run/react-router/blob/e6c53a0130559b4a9bd47f9cf76ea5b08a69868a/packages/react-router/lib/server-runtime/routes.ts#L87
github.com
https://github.com/remix-run/react-router/commit/c84302972a152d851cf5dd859ff332b354b70111
github.com
https://github.com/remix-run/react-router/security/advisories/GHSA-cpj6-fhp6-mr6j
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