Improper access control in Linux kernel - CVE-2026-52920

Vulnerability identifier: #VU135660

CSH Severity: Medium

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

CVE-ID: CVE-2026-52920

CWE-ID: CWE-284

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to bypass inbound IPsec policy matching restrictions.

The vulnerability exists due to improper access control in the xt_policy netfilter matcher when processing strict mode inbound policy matching. A remote attacker can send network traffic that traverses a multi-element inbound rule to bypass inbound IPsec policy matching restrictions.

The issue affects strict matching of multi-element inbound rules.

Linux kernel
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
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Development Tools Module
Basesystem Module
Legacy Module
Public Cloud Module
SUSE Linux Enterprise Live Patching
openEuler
Ubuntu
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-rt (Red Hat package)
bpftool-debuginfo
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-devel
kernel-debugsource
kernel-debuginfo
kernel
perf
perf-debuginfo
python2-perf
python2-perf-debuginfo
python3-perf
python3-perf-debuginfo
bpftool
kernel-headers
kernel (Red Hat package)
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (Ubuntu package)
kernel-default-livepatch
kernel-64kb-devel-debuginfo
kernel-64kb-debugsource
kernel-docs
kernel-syms
kernel-obs-build
kernel-obs-build-debugsource
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-64kb
kernel-default-livepatch-devel
kernel-azure
kernel-azure-devel
kernel-azure-debugsource
cluster-md-kmp-default
gfs2-kmp-default
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-default-extra-debuginfo
kernel-default-devel-debuginfo
kernel-default-debuginfo
ocfs2-kmp-default-debuginfo
dlm-kmp-default-debuginfo
ocfs2-kmp-default
gfs2-kmp-default-debuginfo
dlm-kmp-default
cluster-md-kmp-default-debuginfo
kernel-default-debugsource
kernel-default
kernel-64kb-devel
kernel-default-devel
kernel-macros
kernel-zfcpdump
kernel-zfcpdump-debugsource
kernel-default-extra
kernel-zfcpdump-debuginfo
kernel-64kb-debuginfo
kernel-default-base
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-raspi (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
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-rt (Red Hat package) - update to 4.18.0-553.164.1.rt7.505.el8_10
bpftool-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-tools-devel - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-tools-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-tools - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-source - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-devel - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-debugsource - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
perf - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
perf-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
python2-perf - update to 4.19.90-2608.2.0.0384
python2-perf-debuginfo - update to 4.19.90-2608.2.0.0384
python3-perf - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
python3-perf-debuginfo - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
bpftool - addressed in versions 4.19.90-2608.2.0.0384, 5.10.0-326.0.0.227
kernel-headers - update to 5.10.0-326.0.0.227
kernel (Red Hat package) - update to 5.14.0-687.42.1.el9_8
linux (Ubuntu package) - addressed in versions 5.15.0.184.155, 5.15.0-184.194, 5.15.0-184.194~20.04.1, 5.15.0.186.166, 5.15.0-186.196, 5.15.0-186.196~20.04.1, 5.15.0.1075.78, 5.15.0-1075.79, 5.15.0.1095.94, 5.15.0-1095.103, 5.15.0.1104.100, 5.15.0-1104.109, 5.15.0.1108.107, 5.15.0-1108.114, 5.15.0.1111.115, 5.15.0-1111.120+fips1, 5.15.0.1112.102, 5.15.0.1112.109, 5.15.0-1112.122, 5.15.0-1112.122+fips1, 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, 7.0.0-28.28, 7.0.0-28.28.1, 7.0.0-1003.4, 7.0.0-1008.8
linux-aws (Ubuntu package) - addressed in versions 5.15.0.186.109, 5.15.0-186.196+fips1, 5.15.0.1106.103, 5.15.0-1106.110, 5.15.0.1107.107, 5.15.0-1107.108, 5.15.0.1112.108, 5.15.0.1112.115, 5.15.0-1112.119, 5.15.0-1112.119+fips1, 5.15.0-1112.119~20.04.1, 6.8.0-1061.64+1, 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1053.53, 5.15.0.1053.55, 5.15.0.1064.64, 5.15.0-1064.66
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1064.66~20.04.1
linux-intel-iot-realtime (Ubuntu package) - addressed in versions 5.15.0-1104.106, 5.15.0.1104.108, 5.15.0-1107.113~20.04.1
linux-intel-iotg (Ubuntu package) - addressed in versions 5.15.0.1107.106, 5.15.0-1107.113
linux-azure (Ubuntu package) - addressed in versions 5.15.0.1109.105, 5.15.0-1109.115, 5.15.0.1117.115, 5.15.0-1117.126, 6.8.0-1063.71, 6.8.0-1063.71~22.04.1, 7.0.0-1009.9, 7.0.0-1010.10
linux-azure-5.15 (Ubuntu package) - addressed in versions 5.15.0-1109.115~20.04.1, 5.15.0-1117.126~20.04.1, 5.15.0-1117.126~20.04.2
linux-gcp-5.15 (Ubuntu package) - update to 5.15.0-1112.122~20.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 5.15.0.1117.102, 5.15.0-1117.126+fips1, 6.8.0-1063.71+fips2
linux-azure-fde (Ubuntu package) - addressed in versions 5.15.0-1117.126, 6.8.0-1062.69
kernel-default-livepatch - update to 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.81.1
kernel-docs - update to 6.4.0-150700.53.81.1
kernel-syms - update to 6.4.0-150700.53.81.1
kernel-obs-build - update to 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.81.1
kernel-source - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default - update to 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-64kb - update to 6.4.0-150700.53.81.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.81.1
kernel-azure - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - 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 - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-debuginfo - update to 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - 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 - update to 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
dlm-kmp-default - update to 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.81.1
kernel-default-debugsource - update to 6.4.0-150700.53.81.1
kernel-default - update to 6.4.0-150700.53.81.1
kernel-64kb-devel - update to 6.4.0-150700.53.81.1
kernel-default-devel - update to 6.4.0-150700.53.81.1
kernel-macros - update to 6.4.0-150700.53.81.1
kernel-devel - update to 6.4.0-150700.53.81.1
kernel-zfcpdump - update to 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.81.1
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-64kb-debuginfo - 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
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, 7.0.0-1008.8, 7.0.0-1010.10
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, 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1061.64+fips1, 6.8.0-1061.64~22.04.1
linux-raspi (Ubuntu package) - addressed in versions 6.8.0-1061.65, 6.8.0-2050.52
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1009.9
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

• https://git.kernel.org/stable/c/392cc1d8408b5665215c1e9290bbf0f92339b043
• https://git.kernel.org/stable/c/4b2b4d7d4e203c92db8966b163edfacb1f0e1e29
• https://git.kernel.org/stable/c/82664d0f1ba25e4f9a71994954abae24c60f4067
• https://git.kernel.org/stable/c/938867e870fb5471bb16f442aeac81326e05bf65
• https://git.kernel.org/stable/c/b130a6eefa02bd4d475f2f059da8bcfb3e7d18d9
• https://git.kernel.org/stable/c/eb323f7b82d2e2f638de0cc2a177803eb20e0707
• https://git.kernel.org/stable/c/f98b7f85e04b40e28b08c461ded0cc79f14f5509
• https://git.kernel.org/stable/c/fc1c518bb1f054831ecabb32da9b8e1dff9699c6

• Improper access control in Linux kernel netfilter
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux
• Ubuntu update for linux-gcp-fips
• Ubuntu update for linux-nvidia-tegra-5.15
• Ubuntu update for linux
• Ubuntu update for linux-oracle-6.8
• Ubuntu update for linux-fips
• Ubuntu update for linux-ibm
• Ubuntu update for linux-nvidia-tegra
• Ubuntu update for linux-aws
• Ubuntu update for linux-nvidia
• Ubuntu update for linux-azure
• Ubuntu update for linux-azure-fde
• Ubuntu update for linux-azure
• 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-azure-5.15
• Ubuntu update for linux-hwe-6.8
• Ubuntu update for linux-aws-6.8
• Ubuntu update for linux-ibm
• Ubuntu update for linux-aws
• Ubuntu update for linux-azure-fips
• Ubuntu update for linux-intel-iot-realtime
• Ubuntu update for linux-intel-iotg
• openEuler 22.03 LTS SP4 update for kernel
• openEuler 20.03 LTS SP4 update for kernel
• Ubuntu update for linux-raspi
• Ubuntu update for linux-nvidia-bos
• Ubuntu update for linux-nvidia
• Ubuntu update for linux-gcp-5.15
• Red Hat Enterprise Linux 9 update for kernel
• Ubuntu update for linux-gcp-7.0
• Red Hat Enterprise Linux 8 update for kernel-rt
• SUSE update for the Linux Kernel