CVE-2025-67779 is a high-severity vulnerability in Facebook's React Server Components, specifically in versions 19.0.2, 19.1.3, and 19.2.2. This vulnerability allows unsafe deserialization of payloads from HTTP requests to Server Function endpoints, potentially leading to a denial of service (DoS) situation. The underlying issue stems from an incomplete fix for CVE-2025-55184, which fails to prevent an infinite loop, causing the server process to hang and rendering it incapable of serving future HTTP requests.
The CVSS score for this vulnerability is 7.5, indicating a high severity level. The attack vector is network-based, and the complexity is low, meaning that an attacker does not require special conditions or privileges to exploit the vulnerability. Given the wide use of React in web applications, the risk to organizations includes significant downtime and disruption of services.
Organizations should prioritize patching immediately. The vulnerability has been classified under CWE-400 (Uncontrolled Resource Consumption) and CWE-502 (Deserialization of Untrusted Data). High-profile incidents related to denial of service have highlighted the critical nature of this vulnerability, making it imperative for developers and system administrators to take swift action.
Known exploits for this vulnerability have been identified, emphasizing the urgency for organizations to assess their systems and apply the necessary patches to mitigate risks.
Vulnerability Details
The vulnerability was published on December 12, 2025, and has been classified as modified since then. The official description notes that the fix for CVE-2025-55184 in React Server Components was incomplete, allowing for unsafe deserialization of payloads that can lead to an infinite loop. This impacts the availability of the affected service.
The affected products include React and Next.js. Organizations using these components should review their deployment for the versions specified in the CVE record.
Technical Analysis
The root cause of this vulnerability lies in the deserialization process of payloads from HTTP requests to Server Function endpoints in React Server Components. If an attacker can manipulate the payload, it could cause the server to enter an infinite loop, which effectively denies service to legitimate requests. The attack vector is classified as network-based with low complexity, meaning that attackers can exploit this vulnerability without requiring extensive privileges or user interaction.
The impacts on confidentiality and integrity are rated as none, while the availability impact is high, which indicates that the service may become entirely unavailable due to the resource consumption caused by the attack.
Risk & Impact Analysis
The deployment of React Server Components in production environments poses a risk to organizations, particularly those relying on high availability. The potential for denial of service can severely disrupt business operations, leading to lost revenue and customer trust. The blast radius could be extensive, affecting not just the individual service but potentially the entire application ecosystem.
Given the CVSS score of 7.5 and the known exploit status, organizations should assess their risk management strategies and prioritize this vulnerability within their patch management cycles.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | Yes |
Public PoC | Yes |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The affected versions of React are 19.0.2, 19.1.3, and 19.2.2. Additionally, various versions of Next.js, particularly those between 13.3.0 and 16.1.0, are also affected. Organizations should ensure that they are not using any of these vulnerable versions in their deployments.
Mitigation & Remediation
Organizations should prioritize patching their installations of React and Next.js to prevent exploitation of this vulnerability. Upgrading to the latest stable versions that address this issue is critical. If immediate patching is not feasible, implementing configuration hardening measures and network controls to limit exposure could reduce risk.
For comprehensive security validation, organizations can engage in penetration testing to identify any potential weaknesses in their systems.
Detection Guidance
Monitoring logs for unusual patterns of resource consumption and server behavior can help detect potential exploitation of this vulnerability. Behavioral anomalies should also be tracked, particularly during periods of high traffic.
AppSecure Threat Intelligence Insight
This vulnerability highlights the ongoing challenges in maintaining secure coding practices within rapidly evolving frameworks like React and Next.js. Security teams should remain vigilant in monitoring for similar patterns as vulnerabilities arise, particularly those that can exploit deserialization issues.
Organizations should also consider adopting a proactive approach to security, including regular security assessments and engaging in application security assessments to identify and mitigate risks before they can be exploited.
In conclusion, staying informed about vulnerabilities like CVE-2025-67779 and taking action promptly is essential for safeguarding systems against potential threats. Engaging in red teaming services can provide an additional layer of assurance against such vulnerabilities.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)