Bug 2536537 (CVE-2026-92522)

Summary:	CVE-2026-92522 kernel: ACPI: processor: validate MADT IOAPIC entry bounds
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:	akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, 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 handling of ACPI (Advanced Configuration and Power Interface) tables, specifically within the IOAPIC (I/O Advanced Programmable Interrupt Controller) hotplug lookup. The system did not properly validate the bounds of MADT (Multiple APIC Description Table) and _MAT records. This could lead to an attacker providing malformed ACPI data, potentially causing memory corruption or system instability.	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 2026-09-17 18:20:10 UTC

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

ACPI: processor: validate MADT IOAPIC entry bounds

The IOAPIC hotplug lookup parses both MADT and _MAT records directly.
The MADT walk previously used a subtable's declared length to advance
the cursor after only locating a generic header.  The _MAT path likewise
passed a generic header to the IOAPIC helper.

Validate that a current record has a complete generic header, that its
declared length is contained in the available record range, and that a
typed IOAPIC record contains the full fixed IOAPIC body before reading
its fields.  Use the same relation for both MADT and _MAT provider
paths.

Comment 1 gkamathe 2026-09-19 18:17:58 UTC

Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-92522.mbox