Bug 2502547 (CVE-2026-64042)

Summary:	CVE-2026-64042 kernel: vfio/pci: Check BAR resources before exporting a DMABUF
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:	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 vfio/pci subsystem. This vulnerability occurs because the Direct Memory Access Buffer (DMABUF) export mechanism does not adequately verify if Base Address Register (BAR) resources are properly reserved before allowing access. A local attacker could exploit this by exporting a DMABUF, potentially gaining unauthorized access to unreserved system resources. This could lead to information disclosure or other unintended system behavior.	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 2026-07-19 17:05:27 UTC

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

vfio/pci: Check BAR resources before exporting a DMABUF

A DMABUF exports access to BAR resources and, although they are
requested at startup time, we need to ensure they really were reserved
before exporting.  Otherwise, it's possible to access unreserved
resources through the export.

Add a check to the DMABUF-creation path.

Comment 1 TEJ RATHI 2026-07-20 13:47:35 UTC

Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026071906-CVE-2026-64042-c30f@gregkh/T

Comment 5 errata-xmlrpc 2026-09-08 11:35:22 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:65334 https://access.redhat.com/errata/RHSA-2026:65334