Executive brief
A critical vulnerability exists in Meta's React Server Components, a technology used to build modern web applications. An attacker can remotely take control of a web server by sending a specially crafted request to the application's server-side functions. This flaw is being actively exploited in the wild and can lead to full system compromise, data theft, or service disruption.
Technical details
A remote code execution (RCE) vulnerability exists in React Server Components (RSC) due to the unsafe deserialization of untrusted data (CWE-502). The flaw resides in how the library decodes payloads sent to React Server Function endpoints via HTTP requests. An unauthenticated remote attacker can exploit this by sending a malicious payload to these endpoints, leading to arbitrary code execution on the server. The vulnerability affects the react-server-dom-parcel, react-server-dom-turbopack, and react-server-dom-webpack packages. This issue has been observed being exploited in the wild by threat actors. Patches are available from Meta and in downstream frameworks like Next.js.
Affected products
- Meta React Server Components 19.0.0, 19.1.0, 19.1.1, 19.2.0
- Vercel Next.js 15.0.0 to 15.0.4, 15.1.0 to 15.1.8, 15.2.0 to 15.2.5, 15.3.0 to 15.3.5, 15.4.0 to 15.4.7, 15.5.0 to 15.5.6, 15.6.0, 16.0.0 to 16.0.6
Timeline
- 2025-12-03: advisory: Vendor advisory and patch published by Meta
- 2025-12-05: disclosed: CVE-2025-55182 published
- 2025-12-05: kev added: Added to CISA Known Exploited Vulnerabilities catalog