CVE-2026-23864

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.

## Impact It was found that the fixes to address DoS in React Server Components were incomplete and we found multiple denial of service vulnerabilities still exist in React Server Components. We recommend updating immediately. The vulnerability exists in versions 19.0.0, 19.0.1, 19.0.2, 19.0.3, 19.1.0, 19.1.1, 19.1.2, 19.1.3, 19.1.4, 19.2.0, 19.2.1, 19.2.2, 19.2.3 of: - [react-server-dom-webpack](https://www.npmjs.com/package/react-server-dom-webpack) - [react-server-dom-parcel](https://www.npmjs.com/package/react-server-dom-parcel) - [react-server-dom-turbopack](https://www.npmjs.com/package/react-server-dom-turbopack?activeTab=readme) 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. ## Patches Fixes were back ported to versions 19.0.4, 19.1.5, and 19.2.4. If you are using any of the above packages please upgrade to any of the fixed versions immediately. If your app’s React code does not use a server, your app is not affected by this vulnerability. If your app does not use a framework, bundler, or bundler plugin that supports React Server Components, your app is not affected by this vulnerability. ## References See the [blog post](https://react.dev/blog/2025/12/11/denial-of-service-and-source-code-exposure-in-react-server-components) for more information and upgrade instructions.

## Impact It was found that the fixes to address DoS in React Server Components were incomplete and we found multiple denial of service vulnerabilities still exist in React Server Components. We recommend updating immediately. The vulnerability exists in versions 19.0.0, 19.0.1, 19.0.2, 19.0.3, 19.1.0, 19.1.1, 19.1.2, 19.1.3, 19.1.4, 19.2.0, 19.2.1, 19.2.2, 19.2.3 of: - [react-server-dom-webpack](https://www.npmjs.com/package/react-server-dom-webpack) - [react-server-dom-parcel](https://www.npmjs.com/package/react-server-dom-parcel) - [react-server-dom-turbopack](https://www.npmjs.com/package/react-server-dom-turbopack?activeTab=readme) 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. ## Patches Fixes were back ported to versions 19.0.4, 19.1.5, and 19.2.4. If you are using any of the above packages please upgrade to any of the fixed versions immediately. If your app’s React code does not use a server, your app is not affected by this vulnerability. If your app does not use a framework, bundler, or bundler plugin that supports React Server Components, your app is not affected by this vulnerability. ## References See the [blog post](https://react.dev/blog/2025/12/11/denial-of-service-and-source-code-exposure-in-react-server-components) for more information and upgrade instructions.

Múltiples vulnerabilidades de denegación de servicio existen en los Componentes de Servidor de React, afectando los siguientes paquetes: react-server-dom-parcel, react-server-dom-turbopack, react-server-dom-webpack. Las vulnerabilidades se activan al enviar solicitudes HTTP especialmente diseñadas a los puntos finales de las Funciones de Servidor, y podrían provocar caídas del servidor, excepciones por falta de memoria o uso excesivo de CPU; dependiendo de la ruta de código vulnerable que se esté ejecutando, la configuración de la aplicación y el código de la aplicación. Considere encarecidamente actualizar a las últimas versiones de los paquetes para reducir el riesgo y prevenir problemas de disponibilidad en aplicaciones que utilizan Componentes de Servidor de React.