Reliance on Undefined, Unspecified, or Implementation-Defined Behavior Affecting nodejs package, versions [0,]

Affected versions of this package are vulnerable to Reliance on Undefined, Unspecified, or Implementation-Defined Behavior due to a flaw in error handling when async_hooks (or AsyncLocalStorage) is enabled. Normally, a "Maximum call stack size exceeded" error (stack overflow) is catchable by try-catch blocks or uncaughtException handlers. However, if this error occurs while an async_hooks callback is on the stack (which happens frequently in frameworks like Next.js or when using APM tools), Node.js treats it as a fatal error. Remote attackers can trigger this crash by sending payloads that cause deep recursion (e.g., deeply nested JSON objects), leading to a Denial of Service.

Notes:

1. Node.js 24.x and 25.x are less affected if using only AsyncLocalStorage, as they use a newer V8 feature that avoids this hook mechanism;

2. The patch improves recoverability in one edge case, but it does not remove the broader risk. Recovery from space exhaustion is unspecified, best‑effort behavior and is not a reliable basis for availability or security.

import { createHook } from 'node:async_hooks';

// This simulates what APM tools do
createHook({ init() {} }).enable();

function recursive() {
  new Promise(() => {}); // Creates async context
  return recursive();
}

try {
  recursive();
} catch (err) {
  console.log('This never runs', err);
}

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