Description
It was found that the fix addressing CVE-2025-55184 in React Server Components was incomplete and does not prevent a denial of service attack in a specific case. React Server Components versions 19.0.2, 19.1.3 and 19.2.2 are affected, allowing unsafe deserialization of payloads from HTTP requests to Server Function endpoints. This can cause an infinite loop that hangs the server process and may prevent future HTTP requests from being served.
Affected products
facebook: react; vercel: next.js
References2
- react.dev/blog/2025/12/11/denial-of-service-and-source-code-exp… Vendor Advisory
- www.facebook.com/security/advisories/cve-2025-67779 Vendor Advisory
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 15% percentile: 97 · as of 11 November 2026
- CWE
- CWE-502CWE-400
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.