Input validation error in Linux kernel - CVE-2026-23230
Published: February 19, 2026
Vulnerability identifier: #VU123063
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-2026-23230
CWE-ID: CWE-20
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper input validation within the fs/smb/client/cached_dir.h. A local user can perform a denial of service (DoS) attack.
Affected software
Linux kernel
Debian Linux
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
Ubuntu
openEuler
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
linux (Debian package)
kernel-default-debugsource
kernel-64kb
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-devel
kernel-macros
kernel-default-devel
kernel-default-devel-debuginfo
kernel-default
kernel-default-debuginfo
cluster-md-kmp-default-debuginfo
gfs2-kmp-default
dlm-kmp-default
kernel-default-extra
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
ocfs2-kmp-default
dlm-kmp-default-debuginfo
ocfs2-kmp-default-debuginfo
reiserfs-kmp-default
kernel-default-extra-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
kernel-default-livepatch-devel
kernel-default-livepatch
reiserfs-kmp-default-debuginfo
kernel-64kb-debuginfo
kernel-source
kernel-obs-build-debugsource
kernel-obs-build
kernel-syms
kernel-docs
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
kernel-64kb-devel
kernel-default-base
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel-extra-modules
linux (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
Debian Linux
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
Ubuntu
openEuler
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
linux (Debian package)
kernel-default-debugsource
kernel-64kb
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
kernel-devel
kernel-macros
kernel-default-devel
kernel-default-devel-debuginfo
kernel-default
kernel-default-debuginfo
cluster-md-kmp-default-debuginfo
gfs2-kmp-default
dlm-kmp-default
kernel-default-extra
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
ocfs2-kmp-default
dlm-kmp-default-debuginfo
ocfs2-kmp-default-debuginfo
reiserfs-kmp-default
kernel-default-extra-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
kernel-default-livepatch-devel
kernel-default-livepatch
reiserfs-kmp-default-debuginfo
kernel-64kb-debuginfo
kernel-source
kernel-obs-build-debugsource
kernel-obs-build
kernel-syms
kernel-docs
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
kernel-64kb-devel
kernel-default-base
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel-extra-modules
linux (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
How to mitigate CVE-2026-23230
Install update from vendor's repository.
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
linux (Debian package) - addressed in versions 6.1.164-1, 6.12.73-1
kernel-default-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb - 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-devel - update to 6.4.0-150700.53.81.1
kernel-macros - update to 6.4.0-150700.53.81.1
kernel-default-devel - update to 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default - update to 6.4.0-150700.53.81.1
kernel-default-debuginfo - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
gfs2-kmp-default - update to 6.4.0-150700.53.81.1
dlm-kmp-default - update to 6.4.0-150700.53.81.1
kernel-default-extra - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default - update to 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default - update to 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-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-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
kernel-default-livepatch - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.81.1
kernel-source - update to 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.81.1
kernel-obs-build - update to 6.4.0-150700.53.81.1
kernel-syms - update to 6.4.0-150700.53.81.1
kernel-docs - update to 6.4.0-150700.53.81.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-devel - update to 6.4.0-150700.53.81.1
kernel-default-base - update to 6.4.0-150700.53.81.1.150700.17.45.1
kernel - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
python3-perf-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
python3-perf - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
perf-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
perf - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-tools-devel - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-tools-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-tools - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-headers - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-devel - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-debugsource - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
bpftool-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
bpftool - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-source - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-extra-modules - update to 6.6.0-145.0.0.141
linux (Ubuntu package) - addressed in versions 6.8.0-134.134, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61+fips1, 6.8.0-1058.61~22.04.1, 6.8.0-1060.61, 6.8.0-1060.63+fips1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69, 6.8.0-1063.69+fips1, 6.8.1-1055.56, 6.8.1-1055.56~22.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 6.8.0-134.134+fips1, 6.8.0-1062.69+fips1
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1029.30
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1045.48, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61.1, 6.8.0-1058.64, 6.8.0-1060.61~22.04.1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69~22.04.1
linux-raspi (Ubuntu package) - update to 6.8.0-1060.64
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2049.50
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
linux (Debian package) - addressed in versions 6.1.164-1, 6.12.73-1
kernel-default-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb - 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-devel - update to 6.4.0-150700.53.81.1
kernel-macros - update to 6.4.0-150700.53.81.1
kernel-default-devel - update to 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default - update to 6.4.0-150700.53.81.1
kernel-default-debuginfo - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
gfs2-kmp-default - update to 6.4.0-150700.53.81.1
dlm-kmp-default - update to 6.4.0-150700.53.81.1
kernel-default-extra - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default - update to 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default - update to 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-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-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
kernel-default-livepatch - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.81.1
kernel-source - update to 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.81.1
kernel-obs-build - update to 6.4.0-150700.53.81.1
kernel-syms - update to 6.4.0-150700.53.81.1
kernel-docs - update to 6.4.0-150700.53.81.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-devel - update to 6.4.0-150700.53.81.1
kernel-default-base - update to 6.4.0-150700.53.81.1.150700.17.45.1
kernel - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
python3-perf-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
python3-perf - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
perf-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
perf - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-tools-devel - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-tools-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-tools - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-headers - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-devel - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-debugsource - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
bpftool-debuginfo - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
bpftool - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-source - addressed in versions 6.6.0-144.0.0.139, 6.6.0-145.0.0.128, 6.6.0-145.0.0.141
kernel-extra-modules - update to 6.6.0-145.0.0.141
linux (Ubuntu package) - addressed in versions 6.8.0-134.134, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61+fips1, 6.8.0-1058.61~22.04.1, 6.8.0-1060.61, 6.8.0-1060.63+fips1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69, 6.8.0-1063.69+fips1, 6.8.1-1055.56, 6.8.1-1055.56~22.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 6.8.0-134.134+fips1, 6.8.0-1062.69+fips1
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1029.30
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1045.48, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61.1, 6.8.0-1058.64, 6.8.0-1060.61~22.04.1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69~22.04.1
linux-raspi (Ubuntu package) - update to 6.8.0-1060.64
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2049.50
External References
Related Security Bulletins
- Input validation error in Linux kernel smb client
- Debian update for linux
- Debian update for linux
- openEuler 24.03 LTS SP1 update for kernel
- openEuler 24.03 LTS SP2 update for kernel
- openEuler 24.03 LTS update for kernel
- Ubuntu update for linux
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-raspi-realtime
- Ubuntu update for linux-raspi
- Ubuntu update for linux-azure-fips
- Ubuntu update for linux-azure-fde-6.8
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-hwe-6.8
- SUSE update for the Linux Kernel