CVE-2026-21714

Description

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.

How to fix CVE-2026-21714

To remediate CVE-2026-21714, upgrade the affected package to a fixed version below.

• —upgrade to 22.22.2-r0 or later
• —upgrade to 20.20.2 or later
• —upgrade to 20.20.2 or later
• —upgrade to 12.22.12~dfsg-1~deb11u8 or later

Is CVE-2026-21714 being exploited?

Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.

Affected packages (4)

• from 0, < 22.22.2-r0
• from 0, < 20.20.2, >= 21.0.0, < 22.22.2, >= 23.0.0, < 24.14.1, >= 25.0.0, < 25.8.2
• from 0, < 20.20.2, >= 21.0.0, < 22.22.2, >= 23.0.0, < 24.14.1, >= 25.0.0, < 25.8.2
• from 0, < 12.22.12~dfsg-1~deb11u8

CVSS scores

References (4)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2026-21714
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2026-21714
• WEBnodejs.org/en/blog/vulnerability/march-2026-security-releases
• WEBnvd.nist.gov/vuln/detail/CVE-2026-21714