CVE-2025-55184: Facebook React

High severity, CVSS 7.5. EPSS: 66.9% chance of exploitation in the next 30 days.

A pre-authentication denial of service vulnerability exists in React Server Components versions 19.0.0, 19.0.1 19.1.0, 19.1.1, 19.1.2, 19.2.0 and 19.2.1, including the following packages: react-server-dom-parcel, react-server-dom-turbopack, and react-server-dom-webpack. The vulnerable code unsafely deserializes payloads from HTTP requests to Server Function endpoints, which can cause an infinite loop that hangs the server process and may prevent future HTTP requests from being served.

Affected products

• Facebook React: from 19.0.0, before 19.0.2 (fixed in 19.0.2); from 19.1.0, before 19.1.3 (fixed in 19.1.3); from 19.2.0, before 19.2.2 (fixed in 19.2.2)
• Vercel Next.js: from 13.3.0, before 14.2.35 (fixed in 14.2.35); from 15.0.0, before 15.0.7 (fixed in 15.0.7); from 15.1.0, before 15.1.11 (fixed in 15.1.11); from 15.2.0, before 15.2.8 (fixed in 15.2.8); from 15.3.0, before 15.3.8 (fixed in 15.3.8); from 15.4.0, before 15.4.10 (fixed in 15.4.10); …

Published 2025-12-11. Last modified 2026-10-07.