Vulnerability record/PUBLISHED/Published Sep 18, 2026 10:54:03 UTC

CVE-2026-81627

A flaw was found in QEMU. The VAPIC setup hypercall in hw/i386/vapic.c does not validate that the writable RAM alias remains within the option ROM window. A privileged guest user on a Q35/KVM machine can position this alias over locked SMRAM, bypassing chipset D_LCK protection and injecting code into System Management Mode memory.

Base score8.2/ 10

SeverityHighCVSS 3.1

Exploitability / impact

CVSS metric breakdown

Vector-derived attributes

Base severityHigh

Attack vectorLocalAV

Attack complexityLowAC

Privileges requiredHighPR

User interactionNoneUI

ScopeChangedS

Confidentiality impactHighC

Integrity impactHighI

Availability impactHighA

CVSS vector stringCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

CVSS communicates standardized severity and impact characteristics. It does not establish whether a system is exploitable in your specific environment.

Record context

CVE Numbering Authorityredhat

Last updatedNov 4, 2026 23:43:17 UTC

PublishedSep 18, 2026 10:54:03 UTC

ReservedAug 27, 2026 09:01:09 UTC

Credits

Red Hat would like to thank Artem Dinaburg (Trail of Bits) for reporting this issue.