CVE-2026-21714: Node.js

Medium severity, CVSS 5.3. EPSS: 0.5% chance of exploitation in the next 30 days.

A memory leak occurs in Node.js HTTP/2 servers when a client sends WINDOW_UPDATE frames on stream 0 (connection-level) that cause the flow control window to exceed the maximum value of 2³¹-1. The server correctly sends a GOAWAY frame, but the Http2Session object is never cleaned up. This vulnerability affects HTTP2 users on Node.js 20, 22, 24 and 25.

Affected products

• Node.js Node.js: up to and including 20.20.1; from 22.0.0, up to and including 22.22.1; from 24.0.0, up to and including 24.14.0; from 25.0.0, up to and including 25.8.1

Published 2026-03-30. Last modified 2026-08-19.