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The vulnerability arises from an incomplete patch for CVE-2025-55184 in React Server Components (RSC), allowing denial of service via resource exhaustion. In RSC, server-side rendering processes serialized data from client requests. The flaw exists in the deserialization logic for component props or state, where specific malformed objects bypass the previous fix. When a server receives crafted GraphQL queries or React props with cyclic references or excessive nesting, the component tree resolution enters an infinite loop or consumes high CPU and memory. This occurs during the rendering pipeline where user input is insufficiently validated before being passed to RSC streams. Attackers can send repeated malicious requests to trigger this condition, leading to server unresponsiveness. The issue affects React versions with RSC enabled, exploiting the serialization/deserialization process in frameworks like Next.js. The incomplete fix failed to handle edge cases in object traversal, allowing recursive structures to cause stack overflow or heap exhaustion.
Platform: React
Version: 19.0.2, 19.1.3, 19.2.2
Vulnerability: Denial of Service
Severity: High
Date: Dec 12, 2025
Prediction: Patched Dec 12, 2025
What Undercode Say:
Analytics:
Bash commands:
npm list react
npm audit react
npm update [email protected]
Codes:
import { renderToPipeableStream } from ‘react-dom/server’;
const maliciousProps = JSON.parse(userInput); // Vulnerable
server.get(‘/rsc’, (req,res) => {
const stream = renderToPipeableStream(Component(maliciousProps));
});
How Exploit:
Craft cyclic object props.
Send recursive GraphQL queries.
Trigger infinite rendering loops.
Protection from this CVE:
Update to patched versions.
Sanitize user input.
Disable unused RSC.
Impact:
Server resource exhaustion.
Application downtime.
Reduced availability.
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Sources:
Reported By: github.com
Extra Source Hub:
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