Out-of-bounds read in Linux kernel - CVE-2026-64247

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Main Vulnerability Database Vulnerabilities #VU139738

Out-of-bounds read in Linux kernel - CVE-2026-64247

Published: July 27, 2026


Vulnerability identifier: #VU139738
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-64247
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

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

The vulnerability exists due to an out-of-bounds read in hv_is_vp_in_sparse_set() when handling a paravirtual TLB flush for an L2 guest with a copied VP ID from the enlightened VMCS. A local user can provide a crafted VP ID value to cause a denial of service.

The issue can also cause KVM to perform an unnecessary TLB flush for an L2 vCPU.


Affected software

Linux kernel
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Micro
SUSE Linux Micro Extras
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
openSUSE Leap
openEuler
Ubuntu
linux (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-realtime (Ubuntu package)
linux-fips (Ubuntu package)
linux-gkeop (Ubuntu package)
linux-gke (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
kernel-livepatch-SLE15-SP6_Update_31-debugsource
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo
kernel-livepatch-6_4_0-150600_23_135-default
kernel-livepatch-SLE15-SP7-RT_Update_20-debugsource
kernel-livepatch-6_4_0-150700_7_75-rt
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-64kb
kernel-obs-build-debugsource
kernel-default-debugsource
kernel-default-devel
kernel-syms
kernel-obs-build
kernel-default
kernel-rt-livepatch
kernel-64kb-debugsource
kernel-64kb-devel
kernel-rt-debugsource
kernel-rt-debuginfo
kernel-rt
kernel-devel-rt
kernel-source-rt
kernel-kvmsmall
kernel-devel
kernel-macros
kernel-default-livepatch
kernel-source
kernel-default-debuginfo
kernel-kvmsmall-debugsource
kernel-kvmsmall-debuginfo
kernel-default-devel-debuginfo
kernel-default-base
kernel-64kb-extra-debuginfo
ocfs2-kmp-64kb
kselftests-kmp-64kb
cluster-md-kmp-64kb
kselftests-kmp-default
kernel-64kb-optional-debuginfo
gfs2-kmp-64kb-debuginfo
kernel-64kb-optional
kernel-docs
cluster-md-kmp-64kb-debuginfo
kernel-64kb-extra
reiserfs-kmp-64kb-debuginfo
dlm-kmp-64kb
ocfs2-kmp-64kb-debuginfo
dlm-kmp-64kb-debuginfo
kernel-64kb-debuginfo
kselftests-kmp-64kb-debuginfo
gfs2-kmp-64kb
kernel-64kb-devel-debuginfo
reiserfs-kmp-64kb
kernel-default-livepatch-devel
cluster-md-kmp-default
kernel-kvmsmall-vdso
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-zfcpdump
kernel-source-vanilla
kernel-docs-html
kernel-kvmsmall-devel-debuginfo
kernel-kvmsmall-devel
kernel-debug-vdso
kernel-default-vdso-debuginfo
kernel-default-vdso
kernel-default-optional
kernel-debug-vdso-debuginfo
kernel-kvmsmall-vdso-debuginfo
kernel-debug-debuginfo
kernel-debug-devel
kernel-debug-debugsource
kernel-debug-devel-debuginfo
kernel-debug
kernel-default-extra-debuginfo
kernel-obs-qa
kernel-default-optional-debuginfo
kselftests-kmp-default-debuginfo
kernel-default-extra
ocfs2-kmp-default
cluster-md-kmp-default-debuginfo
gfs2-kmp-default
ocfs2-kmp-default-debuginfo
gfs2-kmp-default-debuginfo
dlm-kmp-default-debuginfo
dlm-kmp-default
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
kernel-default-base-rebuild
gfs2-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
dlm-kmp-rt-debuginfo
gfs2-kmp-rt
ocfs2-kmp-rt
dlm-kmp-rt
kernel-rt-devel
cluster-md-kmp-rt
kernel-rt-devel-debuginfo
kernel-syms-rt
ocfs2-kmp-rt-debuginfo
kernel-azure
kernel-azure-devel
kernel-azure-debugsource
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
bpftool
kernel-extra-modules
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
kernel
linux-nvidia-tegra (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia-7.0 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-raspi (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-64247

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - addressed in versions 6.8.0-147.147, 7.0.0-31.31~24.04.1, 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12~24.04.1, 7.0.0-1012.12
linux-lowlatency (Ubuntu package) - update to 6.8.0-147.147.1
linux-gcp (Ubuntu package) - update to 6.8.0-1071.79
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1071.79, 7.0.0-1011.11, 7.0.0-1014.14
linux-aws (Ubuntu package) - update to 6.8.0-1067.70
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1067.68, 7.0.0-1013.13
linux-oracle (Ubuntu package) - update to 6.8.0-1064.67
linux-azure-fde (Ubuntu package) - update to 6.8.0-1069.76
linux-realtime (Ubuntu package) - update to 6.8.1-1062.63
linux-fips (Ubuntu package) - update to 6.8.0-147.147+fips1
linux-gkeop (Ubuntu package) - update to 6.8.0-1052.56
linux-gke (Ubuntu package) - update to 6.8.0-1066.74
linux-azure-fips (Ubuntu package) - update to 6.8.0-1071.79+fips1
linux-aws-fips (Ubuntu package) - update to 6.8.0-1067.70+fips1
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1071.79+fips1
kernel-livepatch-SLE15-SP6_Update_31-debugsource - 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-6_4_0-150600_23_135-default - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP7-RT_Update_20-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_75-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_81-default - 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-SLE15-SP7_Update_21-debugsource - update to 1-150700.15.3.1
kernel-64kb - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-syms - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-rt-livepatch - update to 6.4.0-52.1
kernel-64kb-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-devel - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-rt-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-rt-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-rt - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-devel-rt - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-source-rt - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-kvmsmall - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1
kernel-devel - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-macros - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-kvmsmall-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1
kernel-default-devel-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-base - addressed in versions 6.4.0-52.1.21.35, 6.4.0-52.1.21.36, 6.4.0-150600.23.135.1.150600.12.62.4, 6.4.0-150700.53.81.1.150700.17.45.1
kernel-64kb-extra-debuginfo - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
kselftests-kmp-64kb - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb - update to 6.4.0-150600.23.135.1
kselftests-kmp-default - update to 6.4.0-150600.23.135.1
kernel-64kb-optional-debuginfo - update to 6.4.0-150600.23.135.1
gfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-optional - update to 6.4.0-150600.23.135.1
kernel-docs - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
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
dlm-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
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-default-livepatch-devel - 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-kvmsmall-vdso - update to 6.4.0-150600.23.135.1
kernel-zfcpdump-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source-vanilla - update to 6.4.0-150600.23.135.1
kernel-docs-html - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-devel-debuginfo - 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-default-optional - 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-debug-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug - update to 6.4.0-150600.23.135.1
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
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
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
gfs2-kmp-default-debuginfo - 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
dlm-kmp-default - 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
reiserfs-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-base-rebuild - update to 6.4.0-150600.23.135.1.150600.12.62.4
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
gfs2-kmp-rt - update to 6.4.0-150700.7.75.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.75.1
dlm-kmp-rt - update to 6.4.0-150700.7.75.1
kernel-rt-devel - update to 6.4.0-150700.7.75.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.75.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.75.1
kernel-syms-rt - update to 6.4.0-150700.7.75.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
kernel-azure - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
bpftool - update to 6.6.0-145.3.29.160
kernel-extra-modules - update to 6.6.0-145.3.29.160
python3-perf-debuginfo - update to 6.6.0-145.3.29.160
python3-perf - update to 6.6.0-145.3.29.160
perf-debuginfo - update to 6.6.0-145.3.29.160
perf - update to 6.6.0-145.3.29.160
kernel-tools-devel - update to 6.6.0-145.3.29.160
kernel-tools-debuginfo - update to 6.6.0-145.3.29.160
kernel-tools - update to 6.6.0-145.3.29.160
kernel-source - update to 6.6.0-145.3.29.160
kernel-headers - update to 6.6.0-145.3.29.160
kernel-devel - update to 6.6.0-145.3.29.160
kernel-debugsource - update to 6.6.0-145.3.29.160
kernel-debuginfo - update to 6.6.0-145.3.29.160
bpftool-debuginfo - update to 6.6.0-145.3.29.160
kernel - update to 6.6.0-145.3.29.160
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1035.38
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia-7.0 (Ubuntu package) - update to 7.0.0-1018.18~24.04.1
linux-nvidia (Ubuntu package) - update to 7.0.0-1018.18
linux-raspi (Ubuntu package) - update to 7.0.0-1019.19
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2018.18

External References

Related Security Bulletins