Bug 2521421 (CVE-2026-74710)

Summary:	CVE-2026-74710 kernel: xsk: require at least 16 bytes of TX metadata
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	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 the Linux kernel's AF_XDP (eXpress Data Path) component. This vulnerability arises because the AF_XDP mechanism accepts a transmit (TX) metadata length that is smaller than required, allowing the kernel to read beyond its designated memory area. An attacker could potentially exploit this out-of-bounds read to gain unauthorized access to sensitive information, leading to information disclosure.	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:

Description OSIDB Bzimport 2026-08-22 15:44:46 UTC

In the Linux kernel, the following vulnerability has been resolved:

xsk: require at least 16 bytes of TX metadata

AF_XDP accepts a TX metadata length as small as eight bytes, but every
supported request needs the flags plus at least one eight-byte request
field. Such short metadata also lets the kernel read beyond the registered
area.

Require 16 bytes rather than sizeof(struct xsk_tx_metadata) to preserve
compatibility with applications that do not use launch-time metadata.

Comment 1 Keith Grant 2026-08-24 17:50:06 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026082237-CVE-2026-74710-5bcd@gregkh/T