Bug 2510856 (CVE-2026-56846)

Summary:	CVE-2026-56846 nodejs: Node.js: Remote memory exhaustion via HTTP/2 retained header blocks
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	gtanzill, jbuscemi, kaycoth, rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in Node.js's handling of HTTP/2. This vulnerability allows a remote attacker to bypass maxSessionMemory limits by sending specially crafted HTTP/2 retained header blocks. This can lead to memory exhaustion, resulting in a denial of service (DoS) for the affected system.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2512131, 2512132
Bug Blocks:

Description OSIDB Bzimport 2026-08-04 01:01:36 UTC

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**.

Comment 3 errata-xmlrpc 2026-08-31 11:24:11 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:61376 https://access.redhat.com/errata/RHSA-2026:61376

Comment 4 errata-xmlrpc 2026-08-31 12:06:16 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:61377 https://access.redhat.com/errata/RHSA-2026:61377

Comment 5 errata-xmlrpc 2026-08-31 14:24:40 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:61386 https://access.redhat.com/errata/RHSA-2026:61386

Comment 6 errata-xmlrpc 2026-08-31 14:28:38 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:61383 https://access.redhat.com/errata/RHSA-2026:61383

Comment 7 errata-xmlrpc 2026-09-01 19:41:00 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:62219 https://access.redhat.com/errata/RHSA-2026:62219