Out-of-bounds write in Linux kernel - CVE-2026-53176

Vulnerability identifier: #VU135620

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-53176

CWE-ID: CWE-787

Exploitation vector: Remote access

Exploit availability: No public exploit available

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

The vulnerability exists due to an out-of-bounds write in isert_login_recv_done() and isert_rx_login_req() in drivers/infiniband/ulp/isert/ib_isert.c when processing a login PDU shorter than ISER_HEADERS_LEN. A remote attacker can send a specially crafted login send work request to cause a denial of service.

The vulnerable code path is reachable during the login phase before iSCSI authentication.

Linux kernel
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
Ubuntu
Public Cloud Module
SUSE Linux Enterprise Live Patching
Legacy Module
Development Tools Module
Basesystem Module
SUSE Real Time 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-aws-hwe (Ubuntu package)
linux-oracle (Ubuntu package)
linux-azure (Ubuntu package)
bpftool
kernel
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python2-perf
python2-perf-debuginfo
python3-perf
kernel-tools
kernel-source
kernel-devel
kernel-debugsource
python3-perf-debuginfo
kernel-debuginfo
bpftool-debuginfo
kernel-headers
linux-nvidia-tegra-igx (Ubuntu package)
linux-azure-fde-5.15 (Ubuntu package)
dlm-kmp-rt-debuginfo
kernel-rt-devel-debuginfo
ocfs2-kmp-rt
gfs2-kmp-rt
kernel-rt-devel
gfs2-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-syms-rt
ocfs2-kmp-rt-debuginfo
kernel-rt-debugsource
cluster-md-kmp-rt
dlm-kmp-rt
kernel-rt
kernel-rt-debuginfo
kernel-source-rt
kernel-devel-rt
kernel-macros
kernel-syms
kernel-docs
kernel-obs-build-debugsource
cluster-md-kmp-default
gfs2-kmp-default
gfs2-kmp-default-debuginfo
ocfs2-kmp-default-debuginfo
kernel-obs-build
reiserfs-kmp-default-debuginfo
reiserfs-kmp-default
dlm-kmp-default-debuginfo
dlm-kmp-default
cluster-md-kmp-default-debuginfo
ocfs2-kmp-default
kernel-zfcpdump
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-default
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-extra
kernel-default-livepatch-devel
kernel-default-livepatch
kernel-azure
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-devel
kernel-azure-debugsource
kernel-default-extra-debuginfo
kernel-default-debugsource
kernel-default-base
linux-lowlatency (Ubuntu package)
linux-azure-6.17 (Ubuntu package)
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 3.13.0.215.225, 3.13.0-215.266, 4.15.0.254.238, 4.15.0-254.266, 4.15.0.1150.147, 4.15.0-1150.162, 4.15.0.1177.168, 4.15.0-1177.182, 4.15.0.1188.201~16.04.1, 4.15.0-1188.205, 4.15.0.1195.193, 4.15.0-1195.208, 4.15.0.1205.173, 4.15.0-1205.220, 4.15.0.2096.94, 4.15.0-2096.102, 4.15.0.2113.109, 4.15.0-2113.119, 4.15.0.2133.127, 4.15.0-2133.139, 5.15.0.187.167, 5.15.0-187.197, 5.15.0.1065.65, 5.15.0-1065.67, 5.15.0-1065.67~20.04.1, 5.15.0.1076.79~20.04.1, 5.15.0-1076.80, 5.15.0.1096.95, 5.15.0-1096.104, 5.15.0.1105.101, 5.15.0-1105.107, 5.15.0.1105.109, 5.15.0-1105.110, 5.15.0.1107.104, 5.15.0.1107.111, 5.15.0-1107.111~20.04.1, 5.15.0.1108.107, 5.15.0.1108.108, 5.15.0-1108.109, 5.15.0-1108.114, 5.15.0-1108.114~20.04.1, 5.15.0-1110.116~20.04.1, 5.15.0.1112.116, 5.15.0-1112.121, 5.15.0.1113.109, 5.15.0.1113.116, 5.15.0-1113.120, 5.15.0-1113.120+fips1, 5.15.0.1118.103, 5.15.0.1118.116, 5.15.0-1118.127, 5.15.0-1118.127+fips1, 6.8.0-137.137+fips1, 6.8.0-1034.35, 6.8.0-1047.51, 6.8.0-1060.63.1, 6.8.0-1060.63~22.04.1, 6.8.0-1060.68, 6.8.0-1062.63, 6.8.0-1062.63~22.04.1, 6.8.0-1062.65, 6.8.0-1062.65+fips1, 6.8.0-1063.70, 6.8.0-1063.70~22.04.1, 6.8.0-1064.72+fips1, 6.8.0-1064.72~22.04.1, 6.8.0-1065.73, 6.8.0-1065.73+fips1, 6.8.0-1065.73~22.04.1, 6.8.1-1057.58, 6.8.1-1057.58~22.04.1, 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-aws-hwe (Ubuntu package) - addressed in versions 4.15.0-254.266~16.04.1, 4.15.0-1188.205~16.04.1, 4.15.0-1195.208~16.04.1, 4.15.0-1205.220~16.04.1
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, 5.15.0.1110.106, 5.15.0-1110.116
linux-azure (Ubuntu package) - update to 4.15.0-1205.220~14.04.1
bpftool - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-tools-debuginfo - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-tools-devel - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
perf - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
perf-debuginfo - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
python2-perf - update to 4.19.90-2607.1.0.0379
python2-perf-debuginfo - update to 4.19.90-2607.1.0.0379
python3-perf - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-tools - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-source - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-devel - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-debugsource - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
python3-perf-debuginfo - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-debuginfo - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
bpftool-debuginfo - addressed in versions 4.19.90-2607.1.0.0379, 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
kernel-headers - addressed in versions 5.10.0-325.0.0.226, 6.6.0-145.1.20.157
linux-nvidia-tegra-igx (Ubuntu package) - addressed in versions 5.15.0-1054.54, 5.15.0.1054.56
linux-azure-fde-5.15 (Ubuntu package) - update to 5.15.0-1118.127~20.04.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
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-devel - update to 6.4.0-150700.7.67.1
gfs2-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
kernel-syms-rt - update to 6.4.0-150700.7.67.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
kernel-rt-debugsource - update to 6.4.0-150700.7.67.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.67.1
dlm-kmp-rt - update to 6.4.0-150700.7.67.1
kernel-rt - update to 6.4.0-150700.7.67.1
kernel-rt-debuginfo - 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-macros - update to 6.4.0-150700.53.73.1
kernel-devel - update to 6.4.0-150700.53.73.1
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-obs-build-debugsource - update to 6.4.0-150700.53.73.2
cluster-md-kmp-default - update to 6.4.0-150700.53.73.2
gfs2-kmp-default - update to 6.4.0-150700.53.73.2
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-obs-build - update to 6.4.0-150700.53.73.2
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
reiserfs-kmp-default - update to 6.4.0-150700.53.73.2
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
dlm-kmp-default - update to 6.4.0-150700.53.73.2
cluster-md-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-zfcpdump-debugsource - update to 6.4.0-150700.53.73.2
kernel-default - update to 6.4.0-150700.53.73.2
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-extra - update to 6.4.0-150700.53.73.2
kernel-default-livepatch-devel - 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
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-debugsource - 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
linux-lowlatency (Ubuntu package) - addressed in versions 6.8.0-137.137.1, 6.8.0-137.137.1~22.04.1, 6.8.0-1031.32, 6.8.0-1059.62
linux-azure-6.17 (Ubuntu package) - addressed in versions 6.17.0-42.42+1, 6.17.0-1019.22, 6.17.0-1022.22, 6.17.0-1022.25, 6.17.0-1032.32
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/1ca40b243277c9e88be5e00bd3e083f71aefb93e
• https://git.kernel.org/stable/c/29e7b925ae6df64894e82ab6419994dc25580a8a
• https://git.kernel.org/stable/c/75ee6e4aa096aa9e7b2dd5c8ff98356e30aceefb
• https://git.kernel.org/stable/c/bd22740d7f14cb1c0289444cfd2c8d2938667c1d
• https://git.kernel.org/stable/c/c1234229399f4af12c553b1b0ffd978eeba65548
• https://git.kernel.org/stable/c/c5584e089b5af7b3bf8bd5e8ca0560cbf32b0a47
• https://git.kernel.org/stable/c/df422fd273c96c2ee5beb80fc21adc8c70c29260
• https://git.kernel.org/stable/c/e8a013c0c3ca2f6708341a56612a3f6d6921620a

• Out-of-bounds write in Linux kernel ulp isert driver
• openEuler 20.03 LTS SP4 update for kernel
• SUSE update for the Linux Kernel
• SUSE update for the Linux Kernel
• openEuler 22.03 LTS SP4 update for kernel
• openEuler 24.03 LTS SP1 update for kernel
• Ubuntu update for linux-azure-6.17
• Ubuntu update for linux-azure
• Ubuntu update for linux
• Ubuntu update for linux
• Ubuntu update for linux
• Ubuntu update for linux
• Ubuntu update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux-oracle
• Ubuntu update for linux-lowlatency
• Ubuntu update for linux-nvidia-tegra-igx
• Ubuntu update for linux-aws-hwe
• Ubuntu update for linux-azure-fde-5.15
• Ubuntu update for linux-aws-7.0
• Ubuntu update for linux-oracle