Out-of-bounds read in Linux kernel - CVE-2026-53246

Vulnerability identifier: #VU135508

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-53246

CWE-ID: CWE-125

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to disclose sensitive information or cause memory corruption.

The vulnerability exists due to an out-of-bounds read in sctp_unpack_cookie() and cached peer INIT chunk processing when processing a crafted COOKIE_ECHO chunk. A remote attacker can send a specially crafted COOKIE_ECHO chunk with an inflated cached INIT chunk length to disclose sensitive information or cause memory corruption.

The issue occurs in a listening SCTP server while walking parameters from the cached peer INIT chunk embedded after the cookie.

Linux kernel
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
Ubuntu
Public Cloud Module
Development Tools Module
Basesystem Module
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Legacy Module
openEuler
kernel-livepatch-6_4_0-150700_7_67-rt
kernel-livepatch-SLE15-SP7-RT_Update_18-debugsource
kernel-livepatch-6_4_0-150700_7_67-rt-debuginfo
kernel-livepatch-SLE15-SP7_Update_19-debugsource
kernel-livepatch-6_4_0-150700_53_73-default
kernel-livepatch-6_4_0-150700_53_73-default-debuginfo
linux (Ubuntu package)
linux-oracle (Ubuntu package)
python3-perf-debuginfo
perf
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
python3-perf
python2-perf-debuginfo
python2-perf
kernel-debugsource
kernel-devel
kernel-source
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf-debuginfo
kernel-rt-devel-debuginfo
ocfs2-kmp-rt
gfs2-kmp-rt
kernel-rt
kernel-source-rt
kernel-devel-rt
kernel-rt-debuginfo
dlm-kmp-rt
cluster-md-kmp-rt
kernel-rt-debugsource
ocfs2-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
gfs2-kmp-rt-debuginfo
kernel-rt-devel
dlm-kmp-rt-debuginfo
kernel-syms-rt
kernel-syms
kernel-docs
kernel-macros
kernel-64kb-debuginfo
kernel-64kb-devel-debuginfo
kernel-64kb-devel
kernel-64kb-debugsource
kernel-64kb
kernel-default-devel-debuginfo
kernel-default-devel
kernel-default-debuginfo
kernel-default-debugsource
ocfs2-kmp-default-debuginfo
kernel-zfcpdump-debugsource
gfs2-kmp-default-debuginfo
kernel-obs-build
kernel-obs-build-debugsource
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-default-extra-debuginfo
kernel-default-extra
gfs2-kmp-default
kernel-default-livepatch-devel
cluster-md-kmp-default
dlm-kmp-default
kernel-default-livepatch
kernel-azure
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-devel
kernel-azure-debugsource
cluster-md-kmp-default-debuginfo
dlm-kmp-default-debuginfo
ocfs2-kmp-default
kernel-zfcpdump
kernel-zfcpdump-debuginfo
kernel-default
kernel-default-base
kernel-headers
linux-oem-7.0 (Ubuntu package)
linux-aws-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-6_4_0-150700_7_67-rt - update to 1-150700.1.5.1
kernel-livepatch-SLE15-SP7-RT_Update_18-debugsource - update to 1-150700.1.5.1
kernel-livepatch-6_4_0-150700_7_67-rt-debuginfo - update to 1-150700.1.5.1
kernel-livepatch-SLE15-SP7_Update_19-debugsource - update to 1-150700.15.3.4
kernel-livepatch-6_4_0-150700_53_73-default - update to 1-150700.15.3.4
kernel-livepatch-6_4_0-150700_53_73-default-debuginfo - update to 1-150700.15.3.4
linux (Ubuntu package) - addressed in versions 3.13.0.217.227, 3.13.0-217.268, 4.15.0.257.241, 4.15.0-257.269, 4.15.0-257.269~16.04.1, 4.15.0.1151.148, 4.15.0-1151.163, 4.15.0.1178.169, 4.15.0-1178.183, 4.15.0.1196.194, 4.15.0-1196.209, 4.15.0-1196.209~16.04.1, 4.15.0.2134.128, 4.15.0-2134.140, 6.8.0-138.138+fips1, 6.8.0-1035.36, 6.8.0-1048.52, 6.8.0-1060.63.1, 6.8.0-1063.66, 6.8.0-1063.66+fips1, 6.8.0-1065.73~22.04.1, 6.8.0-1066.74, 6.8.0-1066.74+fips1, 6.8.0-1066.74~22.04.1, 6.8.1-1058.59, 6.8.1-1058.59~22.04.1, 7.0.0-29.29, 7.0.0-29.29.1, 7.0.0-1009.9, 7.0.0-1010.10, 7.0.0-1011.11, 7.0.0-1016.16
linux-oracle (Ubuntu package) - addressed in versions 4.15.0.1158.163, 4.15.0-1158.169, 4.15.0-1158.169~16.04.1
python3-perf-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
perf - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
bpftool - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
bpftool-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
python3-perf - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
python2-perf-debuginfo - update to 4.19.90-2608.2.0.0384
python2-perf - update to 4.19.90-2608.2.0.0384
kernel-debugsource - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-devel - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-source - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-tools - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-tools-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-tools-devel - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
perf-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 6.6.0-145.1.20.157
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.67.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.67.1
gfs2-kmp-rt - update to 6.4.0-150700.7.67.1
kernel-rt - update to 6.4.0-150700.7.67.1
kernel-source-rt - update to 6.4.0-150700.7.67.1
kernel-devel-rt - update to 6.4.0-150700.7.67.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.67.1
dlm-kmp-rt - update to 6.4.0-150700.7.67.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.67.1
kernel-rt-debugsource - update to 6.4.0-150700.7.67.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
kernel-rt-devel - update to 6.4.0-150700.7.67.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
kernel-syms-rt - update to 6.4.0-150700.7.67.1
kernel-syms - update to 6.4.0-150700.53.73.1
kernel-docs - update to 6.4.0-150700.53.73.1
kernel-source - update to 6.4.0-150700.53.73.1
kernel-macros - update to 6.4.0-150700.53.73.1
kernel-devel - update to 6.4.0-150700.53.73.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.73.2
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.73.2
kernel-64kb-devel - update to 6.4.0-150700.53.73.2
kernel-64kb-debugsource - update to 6.4.0-150700.53.73.2
kernel-64kb - update to 6.4.0-150700.53.73.2
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-devel - update to 6.4.0-150700.53.73.2
kernel-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-debugsource - update to 6.4.0-150700.53.73.2
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.73.2
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-obs-build - update to 6.4.0-150700.53.73.2
kernel-obs-build-debugsource - update to 6.4.0-150700.53.73.2
reiserfs-kmp-default - update to 6.4.0-150700.53.73.2
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-extra - update to 6.4.0-150700.53.73.2
gfs2-kmp-default - update to 6.4.0-150700.53.73.2
kernel-default-livepatch-devel - update to 6.4.0-150700.53.73.2
cluster-md-kmp-default - update to 6.4.0-150700.53.73.2
dlm-kmp-default - update to 6.4.0-150700.53.73.2
kernel-default-livepatch - update to 6.4.0-150700.53.73.2
kernel-azure - update to 6.4.0-150700.53.73.2
kernel-azure-debuginfo - update to 6.4.0-150700.53.73.2
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.73.2
kernel-azure-devel - update to 6.4.0-150700.53.73.2
kernel-azure-debugsource - update to 6.4.0-150700.53.73.2
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
ocfs2-kmp-default - update to 6.4.0-150700.53.73.2
kernel-zfcpdump - update to 6.4.0-150700.53.73.2
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default - update to 6.4.0-150700.53.73.2
kernel-default-base - update to 6.4.0-150700.53.73.2.150700.17.41.4
kernel-headers - update to 6.6.0-145.1.20.157
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1010.10
linux-aws-7.0 (Ubuntu package) - update to 7.0.0-1010.10~24.04.1

• https://git.kernel.org/stable/c/0861615c28de668669d748ef4eb913ea9262d13b
• https://git.kernel.org/stable/c/cc272185c9a9a4b7febc2de52eeaa3d00f19091e
• https://git.kernel.org/stable/c/edccbf3d63b0a3362bc916ea72edacc1e1ca456a

• Out-of-bounds read in Linux kernel sctp
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• openEuler 24.03 LTS SP1 update for kernel
• openEuler 20.03 LTS SP4 update for kernel
• Ubuntu update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux-aws-7.0
• Ubuntu update for linux
• Ubuntu update for linux-oracle
• Ubuntu update for linux
• Ubuntu update for linux