A flaw in Node.js HTTP/2 handling can cause HTTP/2 retained header blocks evade maxSessionMemory and enable remote memory exhaustion. This vulnerability affects Node.js **24.x** and **22.x**.
History

Fri, 07 Aug 2026 10:00:00 +0000

Type Values Removed Values Added
First Time appeared Nodejs
Nodejs nodejs
Vendors & Products Nodejs
Nodejs nodejs

Fri, 07 Aug 2026 00:15:00 +0000

Type Values Removed Values Added
Title Node.js HTTP/2 Memory Exhaustion via Header Block Bypass nodejs: Node.js: Remote memory exhaustion via HTTP/2 retained header blocks
First Time appeared Redhat
Redhat hummingbird
CPEs cpe:/a:redhat:hummingbird:1
Vendors & Products Redhat
Redhat hummingbird
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Important


Tue, 04 Aug 2026 22:00:00 +0000

Type Values Removed Values Added
Title Node.js HTTP/2 Memory Exhaustion via Header Block Bypass

Tue, 04 Aug 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 04 Aug 2026 01:00:00 +0000

Type Values Removed Values Added
Description A flaw in Node.js HTTP/2 handling can cause HTTP/2 retained header blocks evade maxSessionMemory and enable remote memory exhaustion. This vulnerability affects Node.js **24.x** and **22.x**.
Weaknesses CWE-400
References
Metrics cvssV3_0

{'score': 7.5, 'vector': 'CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: hackerone

Published: 2026-08-04T00:49:58.319Z

Updated: 2026-08-04T15:03:38.709Z

Reserved: 2026-06-23T15:00:03.632Z

Link: CVE-2026-56846

cve-icon Vulnrichment

Updated: 2026-08-04T14:28:26.525Z

cve-icon NVD

Status : Received

Published: 2026-08-04T01:16:19.840

Modified: 2026-08-04T16:16:25.710

Link: CVE-2026-56846

cve-icon Redhat

Severity : Important

Publid Date: 2026-08-04T00:49:58Z

Links: CVE-2026-56846 - Bugzilla