CVE-2026-21714

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.

Score

CVSS 3.0 5.3 Medium

Status

Analyzed - support@hackerone.com

Published

2026-03-30

Last modified

2026-03-31

Weaknesses

CWE-401

Affected products

• Node (Nodejs)
• Node.js (Nodejs)

References

• https://nodejs.org/en/blog/vulnerability/march-2026-security-releases