What is CVE-2026-21714?

CVE-2026-21714 is a medium-severity vulnerability in Node.js Node, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 5.3/10. Published 2026-03-30.

How severe is CVE-2026-21714?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Node.js Node

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.

Published 2026-03-30 · last modified 2026-08-19.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.005 (36.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 36.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Node.js Node — versions 20.20.1, 22.22.1, 24.14.0
Node.js

Weakness classification (CWE)

CWE-401 — Missing Release of Memory after Effective Lifetime

References

nodejs.org/en/blog/vulnerability/march-2026-security-releases (Vendor Advisory)

Frequently asked questions

What is CVE-2026-21714?: CVE-2026-21714 is a medium-severity vulnerability in Node.js Node, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 5.3/10. Published 2026-03-30.
How severe is CVE-2026-21714?: Medium severity. CVSS v3 base score is 5.3 out of 10.