Out-of-bounds read in Linux kernel - CVE-2026-64448
Published: July 27, 2026
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in smb2_check_message() and subsequent SMB client protocol decoders when processing crafted SMB2 responses with a data area. A remote attacker can send a specially crafted SMB server response to disclose sensitive information.
The issue is reachable during NEGOTIATE and SESSION_SETUP before the session is established, including through the SPNEGO/negTokenInit and NTLMSSP challenge decoders when mounting against a non-conforming server.
Affected software
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Micro
SUSE Linux Micro Extras
SUSE Linux Enterprise Live Patching
Public Cloud Module
SUSE Real Time Module
Basesystem Module
Development Tools Module
Legacy Module
Ubuntu
openEuler
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-igx (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-azure (Ubuntu package)
linux-gcp (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)
kgraft-patch-4_12_14-122_333-default
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo
kernel-livepatch-6_4_0-150700_7_75-rt
kernel-livepatch-SLE15-SP7-RT_Update_20-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-default
kernel-default-man
kernel-devel
kernel-source
kernel-macros
kernel-default-devel-debuginfo
gfs2-kmp-default
gfs2-kmp-default-debuginfo
kernel-default-devel
cluster-md-kmp-default-debuginfo
kernel-default-kgraft
kernel-default-debugsource
kernel-default-kgraft-devel
kernel-default-debuginfo
dlm-kmp-default
dlm-kmp-default-debuginfo
ocfs2-kmp-default
cluster-md-kmp-default
kernel-default-base-debuginfo
kernel-syms
kernel-default-base
ocfs2-kmp-default-debuginfo
kernel-obs-build
kernel-64kb-devel
kernel-64kb-debugsource
kernel-64kb
kernel-obs-build-debugsource
kernel-kvmsmall-debuginfo
kernel-kvmsmall-debugsource
kernel-default-livepatch
kernel-rt-livepatch
kernel-rt-debugsource
kernel-rt-debuginfo
kernel-rt
kernel-devel-rt
kernel-source-rt
kernel-kvmsmall
ocfs2-kmp-rt
gfs2-kmp-rt-debuginfo
dlm-kmp-rt
kernel-rt-devel
cluster-md-kmp-rt
kernel-rt-devel-debuginfo
kernel-syms-rt
ocfs2-kmp-rt-debuginfo
gfs2-kmp-rt
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-default-extra
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-default-extra-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
kernel-default-livepatch-devel
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
kernel-docs
kernel-64kb-devel-debuginfo
kernel-64kb-debuginfo
kernel-tools-debuginfo
kernel-debuginfo
kernel-tools
kernel-headers
kernel-extra-modules
kernel-debugsource
bpftool
bpftool-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
python3-perf-debuginfo
kernel
linux-nvidia (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (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-raspi (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-64448
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1070.72, 6.8.0-1036.39+1
linux-nvidia-tegra-igx (Ubuntu package) - update to 5.15.0-1059.59
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1070.72~20.04.1
linux (Ubuntu package) - addressed in versions 5.15.0-195.205~20.04.1, 5.15.0-195.205, 5.15.0-198.208~20.04.1, 5.15.0-198.208+fips1, 5.15.0-1080.84, 5.15.0-1100.108, 5.15.0-1109.111, 5.15.0-1109.114, 5.15.0-1111.115~20.04.1, 5.15.0-1111.115, 5.15.0-1112.118~20.04.1, 5.15.0-1112.118, 5.15.0-1113.119, 5.15.0-1114.120, 5.15.0-1116.125~20.04.1, 5.15.0-1117.124~20.04.1, 5.15.0-1117.124, 5.15.0-1117.124+fips1, 5.15.0-1122.131~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1123.132, 5.15.0-1123.132+fips1, 5.15.0.195.160, 5.15.0.195.205~20.04.1, 5.15.0.198.114, 5.15.0.198.171, 5.15.0.198.208~20.04.1, 5.15.0.1080.83~20.04.1, 5.15.0.1100.99, 5.15.0.1109.105, 5.15.0.1109.113, 5.15.0.1111.108, 5.15.0.1111.115~20.04.1, 5.15.0.1112.111, 5.15.0.1112.118~20.04.1, 5.15.0.1113.112, 5.15.0.1114.110, 5.15.0.1116.120, 5.15.0.1117.113, 5.15.0.1117.120, 5.15.0.1117.124~20.04.1, 5.15.0.1122.131~20.04.1, 5.15.0.1123.107, 5.15.0.1123.121, 5.15.0.1123.132~20.04.1, 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-azure (Ubuntu package) - addressed in versions 6.8.0-1071.79, 7.0.0-1011.11, 7.0.0-1014.14
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1118.128, 5.15.0-1118.128+fips1, 5.15.0.1118.107, 5.15.0.1118.115, 6.8.0-1071.79
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) - addressed in versions 5.15.0-1122.131, 5.15.0.1122.131, 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
kgraft-patch-4_12_14-122_333-default - update to 1-8.3.3
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo - 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-SLE15-SP7-RT_Update_20-debugsource - update to 1-150700.1.3.1
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-default - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-default-man - update to 4.12.14-122.333.2
kernel-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-source - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-macros - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
gfs2-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
kernel-default-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
kernel-default-kgraft - update to 4.12.14-122.333.2
kernel-default-debugsource - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-default-kgraft-devel - update to 4.12.14-122.333.2
kernel-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
dlm-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
ocfs2-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
cluster-md-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
kernel-default-base-debuginfo - update to 4.12.14-122.333.2
kernel-syms - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-default-base - addressed in versions 4.12.14-122.333.2, 6.4.0-52.1.21.35, 6.4.0-52.1.21.36, 6.4.0-150700.53.81.1.150700.17.45.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.81.1
kernel-obs-build - addressed in versions 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-64kb-devel - addressed in versions 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-64kb-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-64kb - addressed in versions 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-kvmsmall-debuginfo - update to 6.4.0-52.1
kernel-kvmsmall-debugsource - update to 6.4.0-52.1
kernel-default-livepatch - addressed in versions 6.4.0-52.1, 6.4.0-150700.53.81.1
kernel-rt-livepatch - update to 6.4.0-52.1
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 - update to 6.4.0-52.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.75.1
gfs2-kmp-rt-debuginfo - 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
gfs2-kmp-rt - update to 6.4.0-150700.7.75.1
dlm-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
kernel-default-extra - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.81.1
kernel-zfcpdump - update to 6.4.0-150700.53.81.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.81.1
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
kernel-default-livepatch-devel - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default - update to 6.4.0-150700.53.81.1
kernel-docs - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.81.1
kernel-tools-debuginfo - update to 6.6.0-145.3.29.160
kernel-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-extra-modules - 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
bpftool - update to 6.6.0-145.3.29.160
bpftool-debuginfo - update to 6.6.0-145.3.29.160
kernel-tools-devel - update to 6.6.0-145.3.29.160
perf - update to 6.6.0-145.3.29.160
perf-debuginfo - update to 6.6.0-145.3.29.160
python3-perf - update to 6.6.0-145.3.29.160
python3-perf-debuginfo - update to 6.6.0-145.3.29.160
kernel - update to 6.6.0-145.3.29.160
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112, 7.0.0-1018.18
linux-oracle-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.120~20.04.1, 5.15.0.1114.120~20.04.1
linux-gcp-5.15 (Ubuntu package) - addressed in versions 5.15.0-1118.128~20.04.1, 5.15.0.1118.128~20.04.1
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-raspi (Ubuntu package) - update to 7.0.0-1019.19
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2018.18
External References
- https://git.kernel.org/stable/c/31c6312608c60b72a1feb99a5afb680645a3e8a3
- https://git.kernel.org/stable/c/419ec1b604d7fb60c10aec2dc062371f9fcd4940
- https://git.kernel.org/stable/c/53b7c271f06be4dd5cfc8c6ef552a8355c891a7f
- https://git.kernel.org/stable/c/573e502d14714d2947e22e7eff40ec20a6a44a42
- https://git.kernel.org/stable/c/6e9d10f62773b99bd927940fd9cbdfe7207e23ff
- https://git.kernel.org/stable/c/8d0bbc78046d264bbf6a574ea6f9072258a43e35
- https://git.kernel.org/stable/c/b6a381c01e2ac98a48e32ac0f2a45bbadd9e26b0
- https://git.kernel.org/stable/c/ceb875a375dedbf51c9425c1d13a2d7a8435c08c
Related Security Bulletins
- Out-of-bounds read in Linux kernel smb client
- openEuler 24.03 LTS SP3 update for kernel
- Ubuntu update for linux-oem-7.0
- Ubuntu update for linux
- Ubuntu update for linux-gcp-7.0
- SUSE update for the Linux Kernel
- Ubuntu update for linux-oracle-7.0
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure-7.0
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-nvidia-bos
- Ubuntu update for linux-ibm
- Ubuntu update for linux-raspi
- Ubuntu update for linux-nvidia-7.0
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-gcp
- Ubuntu update for linux-gcp-5.15
- Ubuntu update for linux-oracle-5.15
- Ubuntu update for linux
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- Ubuntu update for linux, linux-aws, linux-aws-fips and more
- Ubuntu update for linux-azure, linux-azure-fde, linux-azure-fips
- Ubuntu update for linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx