Critical React Server Components RCE Hits Next.js and Related Ecosystem
A critical remote code execution vulnerability in React Server Components-related packages is affecting widely used parts of the React ecosystem, including deployments tied to Next.js, React Router, Expo, Redwood SDK, Waku, and @vitejs/plugin-rsc. The flaw allows an unauthenticated attacker to execute arbitrary code on a vulnerable system through an HTTP request. Affected versions include 19.0, 19.1.0, 19.1.1, and 19.2.0 of react-server-dom-webpack, react-server-dom-parcel, and react-server-dom-turbopack, while patched releases are 19.0.1, 19.1.2, and 19.2.1.
Authorities warned that exploitation is already active in Finland and that public exploit methods are available, increasing the likelihood of rapid opportunistic attacks against exposed applications. Officials said attackers may use the vulnerability not only for visible abuse such as cryptomining but also to establish persistent access, and urged organizations to patch immediately and assess internet-exposed systems for signs of compromise.
Timeline
Dec 4, 2025
Active exploitation of React RCE observed in Finland
Finnish authorities reported active exploitation in Finland of the critical React Server Components vulnerability. They warned attackers may use the flaw for visible activity such as cryptomining as well as to establish persistent access, and urged immediate patching and compromise assessment of exposed systems.
Dec 4, 2025
Public exploit methods emerge for React Server Components flaw
Public exploitation methods became available for the critical React Server Components vulnerability, lowering the barrier to abuse. The flaw impacts products identified by React such as Next.js, React Router, Expo, Redwood SDK, Waku, and @vitejs/plugin-rsc, along with potentially other implementations using the affected packages.
Dec 4, 2025
React fixes critical RCE in React Server Components packages
React released patched versions 19.0.1, 19.1.2, and 19.2.1 for the affected react-server-dom-webpack, react-server-dom-parcel, and react-server-dom-turbopack packages. The vulnerability affects versions 19.0, 19.1.0, 19.1.1, and 19.2.0 and can allow unauthenticated remote code execution via an HTTP request.
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