CVE-2026-23864: Facebook React

High severity, CVSS 7.5. EPSS: 2.6% chance of exploitation in the next 30 days.

Multiple denial of service vulnerabilities exist in React Server Components, affecting the following packages: react-server-dom-parcel, react-server-dom-turbopack, react-server-dom-webpack. The vulnerabilities are triggered by sending specially crafted HTTP requests to Server Function endpoints, and could lead to server crashes, out-of-memory exceptions or excessive CPU usage; depending on the vulnerable code path being exercised, the application configuration and application code. Strongly consider upgrading to the latest package versions to reduce risk and prevent availability issues in applications using React Server Components.

Affected products

• Facebook React: from 19.0.0, before 19.0.4 (fixed in 19.0.4); from 19.1.0, before 19.1.5 (fixed in 19.1.5); from 19.2.0, before 19.2.4 (fixed in 19.2.4)

Published 2026-01-26. Last modified 2026-07-15.