Improper access control in Linux kernel - CVE-2026-74516

Vulnerability identifier: #VU143269

CSH Severity: Low

CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-74516

CWE-ID: CWE-284

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper access control in x2APIC MSR interception handling in KVM SVM/AVIC when AVIC is inhibited while an L2 guest is active. A local user can run a nested guest that triggers this state to cause a denial of service.

The issue can allow an L1 guest to read much of the host APIC state, send arbitrary interrupts, and change task priority before host disruption occurs.

Linux kernel
Debian Linux
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Workstation Extension 15
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
SUSE Linux Enterprise Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
openSUSE Leap
kernel-livepatch-6_4_0-150600_23_135-default
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo
kernel-livepatch-SLE15-SP6_Update_31-debugsource
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel (Red Hat package)
kernel-rt (Red Hat package)
dlm-kmp-64kb-debuginfo
kernel-64kb-optional
gfs2-kmp-64kb-debuginfo
kernel-64kb-devel
kernel-64kb-optional-debuginfo
cluster-md-kmp-64kb
kselftests-kmp-64kb
ocfs2-kmp-64kb
kernel-64kb-extra-debuginfo
cluster-md-kmp-64kb-debuginfo
kernel-64kb-extra
reiserfs-kmp-64kb-debuginfo
dlm-kmp-64kb
ocfs2-kmp-64kb-debuginfo
kernel-64kb-debugsource
kernel-64kb-debuginfo
kselftests-kmp-64kb-debuginfo
gfs2-kmp-64kb
kernel-64kb-devel-debuginfo
reiserfs-kmp-64kb
kernel-zfcpdump-debuginfo
kernel-default-livepatch-devel
kernel-zfcpdump-debugsource
kernel-default
kernel-default-livepatch
kernel-docs
kernel-devel
kernel-macros
kernel-debug-devel-debuginfo
kernel-kvmsmall-debuginfo
kernel-kvmsmall-devel-debuginfo
kernel-kvmsmall-debugsource
kernel-kvmsmall-devel
kernel-debug-vdso
kernel-default-vdso-debuginfo
kernel-default-vdso
kernel-kvmsmall-vdso
kernel-debug-vdso-debuginfo
kernel-kvmsmall-vdso-debuginfo
kernel-debug-debuginfo
kernel-debug-devel
kernel-debug-debugsource
kernel-docs-html
kernel-debug
kernel-64kb
kernel-default-extra-debuginfo
kernel-obs-qa
kernel-default-optional-debuginfo
kselftests-kmp-default-debuginfo
kernel-default-extra
kernel-default-optional
kernel-source-vanilla
kselftests-kmp-default
kernel-kvmsmall
kernel-zfcpdump
dlm-kmp-default-debuginfo
ocfs2-kmp-default
cluster-md-kmp-default-debuginfo
kernel-syms
gfs2-kmp-default
ocfs2-kmp-default-debuginfo
kernel-obs-build
kernel-default-debugsource
gfs2-kmp-default-debuginfo
kernel-obs-build-debugsource
reiserfs-kmp-default-debuginfo
kernel-default-devel-debuginfo
dlm-kmp-default
kernel-default-debuginfo
cluster-md-kmp-default
kernel-default-devel
reiserfs-kmp-default
kernel-source
kernel-default-base
kernel-default-base-rebuild
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-6_4_0-150600_23_135-default - update to 1-150600.13.3.4
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP6_Update_31-debugsource - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP7_Update_21-debugsource - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_81-default - update to 1-150700.15.3.1
kernel (Red Hat package) - addressed in versions 4.18.0-553.171.1.el8_10, 5.14.0-687.55.1.el9_8
kernel-rt (Red Hat package) - update to 4.18.0-553.171.1.rt7.512.el8_10
dlm-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-optional - update to 6.4.0-150600.23.135.1
gfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-optional-debuginfo - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb - update to 6.4.0-150600.23.135.1
kselftests-kmp-64kb - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-extra-debuginfo - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-extra - update to 6.4.0-150600.23.135.1
reiserfs-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
dlm-kmp-64kb - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kselftests-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
gfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-devel-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-zfcpdump-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-docs - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-macros - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-debug-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-debugsource - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-devel - update to 6.4.0-150600.23.135.1
kernel-debug-vdso - update to 6.4.0-150600.23.135.1
kernel-default-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-vdso - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso - update to 6.4.0-150600.23.135.1
kernel-debug-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-devel - update to 6.4.0-150600.23.135.1
kernel-debug-debugsource - update to 6.4.0-150600.23.135.1
kernel-docs-html - update to 6.4.0-150600.23.135.1
kernel-debug - update to 6.4.0-150600.23.135.1
kernel-64kb - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-extra-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-qa - update to 6.4.0-150600.23.135.1
kernel-default-optional-debuginfo - update to 6.4.0-150600.23.135.1
kselftests-kmp-default-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-extra - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-optional - update to 6.4.0-150600.23.135.1
kernel-source-vanilla - update to 6.4.0-150600.23.135.1
kselftests-kmp-default - update to 6.4.0-150600.23.135.1
kernel-kvmsmall - update to 6.4.0-150600.23.135.1
kernel-zfcpdump - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-syms - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-base - addressed in versions 6.4.0-150600.23.135.1.150600.12.62.4, 6.4.0-150700.53.81.1.150700.17.45.1
kernel-default-base-rebuild - update to 6.4.0-150600.23.135.1.150600.12.62.4
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure - update to 6.4.0-150700.53.81.1
linux (Debian package) - update to 6.12.105-1

• https://git.kernel.org/stable/c/6664a5aea45318f4ec156a729949b474dd6e3159
• https://git.kernel.org/stable/c/7668c58dcf465559dc7a0d2e95e9cb79cf47454b
• https://git.kernel.org/stable/c/7d3aae206663c4e006b25a1c7a20a4029e67da76
• https://git.kernel.org/stable/c/89f9e8398e79c49886766fc24a84c37726231104
• https://git.kernel.org/stable/c/f12373625b4dc9bcc89c41872648878c73bb9272

• Improper access control in Linux kernel kvm svm
• Debian update for linux
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• Red Hat Enterprise Linux 8 update for kernel-rt
• Red Hat Enterprise Linux 8 update for kernel
• Red Hat Enterprise Linux 9 update for kernel