CVE-2026-21714
Node.js: Node.js: Memory leak and Denial of Service via crafted HTTP/2 WINDOW_UPDATE frames
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · March 31, 2026
Updated · June 30, 2026
Description
A flaw was found in Node.js. A remote attacker can exploit this vulnerability in Node.js HTTP/2 servers by sending specially crafted WINDOW_UPDATE frames on stream 0 (connection-level). These frames can cause the flow control window to exceed its maximum value, leading to a memory leak as Http2Session objects are not properly cleaned up. This can result in resource exhaustion and a Denial of Service (DoS) condition for the server.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE-772 · Missing Release of Resource after Effective Lifetime