Out-of-bounds read in Linux kernel - CVE-2026-23255

Vulnerability identifier: #VU124193

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-2026-23255

CWE-ID: CWE-125

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to improper input validation in the /proc/net/ptype component when handling RCU-protected network device references. A local attacker can exploit a race condition during iteration of packet types to cause a denial of service.

The issue arises from missing RCU protection when accessing pt->dev in ptype_seq_show() and ptype_seq_next(), allowing concurrent modifications to trigger an RCU stall.

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Desktop 15
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 Live Patching
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
SUSE Real Time Module
Ubuntu
openEuler
kgraft-patch-4_12_14-122_320-default
kernel-livepatch-6_4_0-150700_7_37-rt-debuginfo
kernel-livepatch-6_4_0-150700_7_37-rt
kernel-livepatch-SLE15-SP7-RT_Update_11-debugsource
kernel-livepatch-SLE15-SP7_Update_11-debugsource
kernel-livepatch-6_4_0-150700_53_37-default
kernel-livepatch-6_4_0-150700_53_37-default-debuginfo
kernel-default-kgraft-devel
gfs2-kmp-default
ocfs2-kmp-default-debuginfo
kernel-syms
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
kernel-default
kernel-default-devel-debuginfo
ocfs2-kmp-default
kernel-default-kgraft
dlm-kmp-default-debuginfo
kernel-default-debuginfo
dlm-kmp-default
cluster-md-kmp-default-debuginfo
kernel-default-base-debuginfo
kernel-default-debugsource
kernel-default-devel
kernel-source
kernel-macros
kernel-default-base
kernel-default-man
kernel-devel
kernel-syms-rt
cluster-md-kmp-rt
dlm-kmp-rt
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-rt-devel-debuginfo
kernel-rt-devel
ocfs2-kmp-rt
kernel-rt-debugsource
ocfs2-kmp-rt-debuginfo
gfs2-kmp-rt
kernel-rt-debuginfo
gfs2-kmp-rt-debuginfo
kernel-devel-rt
kernel-source-rt
kernel-rt
reiserfs-kmp-default
kernel-zfcpdump
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-docs
kernel-obs-build
kernel-obs-build-debugsource
reiserfs-kmp-default-debuginfo
kernel-azure
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-default-extra-debuginfo
kernel-default-extra
kernel-default-livepatch-devel
kernel-default-livepatch
kernel-64kb
kernel-64kb-devel-debuginfo
kernel-64kb-debuginfo
kernel-64kb-devel
kernel-64kb-debugsource
python3-perf
python3-perf-debuginfo
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
kernel-extra-modules
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kgraft-patch-4_12_14-122_320-default - update to 1-8.3.1
kernel-livepatch-6_4_0-150700_7_37-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_37-rt - update to 1-150700.1.3.1
kernel-livepatch-SLE15-SP7-RT_Update_11-debugsource - update to 1-150700.1.3.1
kernel-livepatch-SLE15-SP7_Update_11-debugsource - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_37-default - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_37-default-debuginfo - update to 1-150700.15.3.1
kernel-default-kgraft-devel - update to 4.12.14-122.320.1
gfs2-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-syms - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
cluster-md-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
gfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
ocfs2-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default-kgraft - update to 4.12.14-122.320.1
dlm-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
dlm-kmp-default - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default-base-debuginfo - update to 4.12.14-122.320.1
kernel-default-debugsource - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default-devel - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-source - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-macros - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-default-base - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1.150700.17.25.1
kernel-default-man - update to 4.12.14-122.320.1
kernel-devel - addressed in versions 4.12.14-122.320.1, 6.4.0-150700.53.37.1
kernel-syms-rt - update to 6.4.0-150700.7.37.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.37.2
dlm-kmp-rt - update to 6.4.0-150700.7.37.2
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.37.2
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.37.2
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.37.2
kernel-rt-devel - update to 6.4.0-150700.7.37.2
ocfs2-kmp-rt - update to 6.4.0-150700.7.37.2
kernel-rt-debugsource - update to 6.4.0-150700.7.37.2
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.37.2
gfs2-kmp-rt - update to 6.4.0-150700.7.37.2
kernel-rt-debuginfo - update to 6.4.0-150700.7.37.2
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.37.2
kernel-devel-rt - update to 6.4.0-150700.7.37.2
kernel-source-rt - update to 6.4.0-150700.7.37.2
kernel-rt - update to 6.4.0-150700.7.37.2
reiserfs-kmp-default - update to 6.4.0-150700.53.37.1
kernel-zfcpdump - update to 6.4.0-150700.53.37.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.37.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.37.1
kernel-docs - update to 6.4.0-150700.53.37.1
kernel-obs-build - update to 6.4.0-150700.53.37.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.37.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.37.1
kernel-azure - update to 6.4.0-150700.53.37.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.37.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.37.1
kernel-azure-debugsource - update to 6.4.0-150700.53.37.1
kernel-azure-devel - update to 6.4.0-150700.53.37.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.37.1
kernel-default-extra - update to 6.4.0-150700.53.37.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.37.1
kernel-default-livepatch - update to 6.4.0-150700.53.37.1
kernel-64kb - update to 6.4.0-150700.53.37.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.37.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.37.1
kernel-64kb-devel - update to 6.4.0-150700.53.37.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.37.1
python3-perf - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
python3-perf-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
perf-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
perf - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-tools-devel - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-tools-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-tools - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-source - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-headers - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-devel - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-debugsource - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
bpftool-debuginfo - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
bpftool - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel - addressed in versions 6.6.0-145.0.2.130, 6.6.0-145.0.2.142, 6.6.0-145.0.2.143
kernel-extra-modules - update to 6.6.0-145.0.2.143
linux (Ubuntu package) - addressed in versions 6.8.0-136.136, 6.8.0-1046.50, 6.8.0-1059.67, 6.8.0-1064.72, 6.8.0-1064.72~22.04.1, 6.8.1-1056.57, 6.8.1-1056.57~22.04.2
linux-fips (Ubuntu package) - addressed in versions 6.8.0-136.136+fips2, 6.8.0-136.136.2, 6.8.0-136.136.2~22.04.1, 6.8.0-1058.61
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1030.31, 6.8.0-1033.34, 6.8.0-1061.62, 6.8.0-1061.62~22.04.1
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1058.61~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1059.62, 6.8.0-1059.62.1, 6.8.0-1059.62~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-aws (Ubuntu package) - update to 6.8.0-1061.64+1
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-azure-fips (Ubuntu package) - update to 6.8.0-1063.71+fips2
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
linux (Debian package) - update to 6.12.85-1

• https://git.kernel.org/stable/c/589a530ae44d0c80f523fcfd1a15af8087f27d35
• https://git.kernel.org/stable/c/f613e8b4afea0cd17c7168e8b00e25bc8d33175d

• Out-of-bounds read in Linux kernel core
• openEuler 24.03 LTS SP2 update for kernel
• openEuler 24.03 LTS SP1 update for kernel
• openEuler 24.03 LTS update for kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• Debian update for linux
• SUSE update for the Linux Kernel
• Ubuntu update for linux
• Ubuntu update for linux-gcp-fips
• Ubuntu update for linux-oracle-6.8
• Ubuntu update for linux-fips
• Ubuntu update for linux-nvidia
• Ubuntu update for linux-azure-fde-6.8
• Ubuntu update for linux-azure-fips
• Ubuntu update for linux-azure-fde
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws
• Ubuntu update for linux-hwe-6.8
• Ubuntu update for linux-aws-6.8
• Ubuntu update for linux-ibm