## Critical RCE Vulnerability in React Server Components Targets Next.js Deployments via Insecure Deserialization
Vercel has generated an automated security pull request addressing a critical remote code execution vulnerability in React Server Components, exposing Next.js applications to unauthenticated server-side attacks. The flaw resides in insecure deserialization within the React Flight protocol, the mechanism underlying server component streaming in modern React frameworks. Security advisories across multiple platforms—GitHub (GHSA-9qr9-h5gf-34mp), React (CVE-2025-55182), and Next.js (CVE-2025-66478)—are tracking the exposure, which specifically impacts the portfolio-nextjs project hosted on Vercel.

The vulnerability enables threat actors to execute arbitrary code on affected servers without authentication, representing a severe threat vector given the ubiquity of Next.js deployments in production environments. React Server Components leverage the Flight protocol to serialize and deserialize component data between server and client, and the identified flaw allows malicious payloads to be injected during this process. While Vercel's automated PR aims to patch the exposure, the company has explicitly stated it cannot guarantee comprehensive remediation and advises developers to conduct thorough manual review before merging changes.

Organizations running Next.js with React Server Components enabled face immediate pressure to evaluate their deployments for exposure. The cross-platform nature of the advisories signals coordinated disclosure efforts, yet the reliance on automated fixes raises questions about whether full mitigation requires additional configuration changes or dependency updates. Developers are urged to consult Vercel's supplementary guidance and monitor for further updates from the React and Next.js security teams.
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- **Source**: GitHub Issues
- **Sector**: The Lab
- **Tags**: RCE vulnerability, React Server Components, Next.js, Vercel, insecure deserialization
- **Credibility**: unverified
- **Published**: 2026-04-22 10:27:37
- **ID**: 75897
- **URL**: https://whisperx.ai/en/intel/75897