Out-of-bounds read in Linux kernel - CVE-2026-52986

Vulnerability identifier: #VU135388

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-2026-52986

CWE-ID: CWE-125

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 out-of-bounds read in the nf_conntrack_sip SIP message parser when parsing non-NUL-terminated SIP packet data containing crafted port values. A remote attacker can send a specially crafted SIP packet to cause a denial of service.

The issue involves port parsing in epaddr_len(), ct_sip_parse_header_uri(), and ct_sip_parse_request(), where parsing could reach the buffer limit without a trailing character.

Linux kernel
SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME
SUSE Linux Enterprise Server 11
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
Red Hat Enterprise Linux for IBM z Systems
Ubuntu
openEuler
kernel-xen-devel-debuginfo
kernel-default-devel-debuginfo
kernel-default-devel
kernel-ec2-devel
kernel-trace-debugsource
kernel-xen-devel
kernel-default-base
kernel-trace-devel
kernel-default-debuginfo
kernel-xen-debuginfo
kernel-ec2-base
kernel-xen-base
kernel-trace-debuginfo
kernel-trace-base
kernel-ec2-devel-debuginfo
kernel-xen-debugsource
kernel-ec2-debugsource
kernel-default-debugsource
kernel-source
kernel-docs
kernel-xen
kernel-default
kernel-trace
kernel-ec2
kernel-syms
kernel-ec2-debuginfo
kernel-trace-devel-debuginfo
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-aws-hwe (Ubuntu package)
linux-oracle (Ubuntu package)
linux-azure (Ubuntu package)
kernel (Red Hat package)
kernel-rt (Red Hat package)
linux-kvm (Ubuntu package)
linux-oracle-5.4 (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-azure-5.4 (Ubuntu package)
bpftool
perf-debuginfo
bpftool-debuginfo
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
kernel-tools
kernel-tools-debuginfo
kernel
kernel-tools-devel
perf
python3-perf-debuginfo
python3-perf
linux-aws (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-intel-iot-realtime (Ubuntu package)
linux-raspi (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (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-azure-fde-6.8 (Ubuntu package)
linux-nvidia-6.17 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-xen-devel-debuginfo - update to 3.0.101-108.216.1
kernel-default-devel-debuginfo - update to 3.0.101-108.216.1
kernel-default-devel - update to 3.0.101-108.216.1
kernel-ec2-devel - update to 3.0.101-108.216.1
kernel-trace-debugsource - update to 3.0.101-108.216.1
kernel-xen-devel - update to 3.0.101-108.216.1
kernel-default-base - update to 3.0.101-108.216.1
kernel-trace-devel - update to 3.0.101-108.216.1
kernel-default-debuginfo - update to 3.0.101-108.216.1
kernel-xen-debuginfo - update to 3.0.101-108.216.1
kernel-ec2-base - update to 3.0.101-108.216.1
kernel-xen-base - update to 3.0.101-108.216.1
kernel-trace-debuginfo - update to 3.0.101-108.216.1
kernel-trace-base - update to 3.0.101-108.216.1
kernel-ec2-devel-debuginfo - update to 3.0.101-108.216.1
kernel-xen-debugsource - update to 3.0.101-108.216.1
kernel-ec2-debugsource - update to 3.0.101-108.216.1
kernel-default-debugsource - update to 3.0.101-108.216.1
kernel-source - update to 3.0.101-108.216.1
kernel-docs - update to 3.0.101-108.216.1
kernel-xen - update to 3.0.101-108.216.1
kernel-default - update to 3.0.101-108.216.1
kernel-trace - update to 3.0.101-108.216.1
kernel-ec2 - update to 3.0.101-108.216.1
kernel-syms - update to 3.0.101-108.216.1
kernel-ec2-debuginfo - update to 3.0.101-108.216.1
kernel-trace-devel-debuginfo - update to 3.0.101-108.216.1
linux (Ubuntu package) - addressed in versions 3.13.0.215.225, 3.13.0-215.266, 4.4.0.284.290, 4.4.0-284.318, 4.4.0-284.318~14.04.1, 4.4.0.1157.154, 4.4.0-1157.163, 4.4.0.1158.155, 4.4.0-1158.169, 4.4.0.1195.199, 4.4.0-1195.210, 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, 5.4.0.234.226, 5.4.0-234.254, 5.4.0-234.254~18.04.1, 5.4.0-1066.69, 5.4.0.1080.80, 5.4.0-1080.84, 5.4.0-1108.113, 5.4.0-1108.113~18.04.1, 5.4.0.1108.137, 5.4.0.1121.117, 5.4.0-1121.128, 5.4.0.1136.133, 5.4.0-1136.146, 5.4.0-1145.158, 5.4.0-1145.158~18.04.1, 5.4.0.1145.176, 5.4.0.1160.154, 5.4.0-1160.170+fips1, 5.4.0.1162.160, 5.4.0-1162.173, 5.4.0-1162.173~18.04.1, 5.4.0.1165.167, 5.4.0-1165.174, 5.4.0-1165.174~18.04.1, 5.4.0.1167.159, 5.4.0-1167.173, 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-fips (Ubuntu package) - addressed in versions 4.4.0.1127.129, 4.4.0-1127.134, 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-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
linux-azure (Ubuntu package) - addressed in versions 4.15.0-1205.220~14.04.1, 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
kernel (Red Hat package) - update to 4.18.0-553.162.1.el8_10
kernel-rt (Red Hat package) - update to 4.18.0-553.162.1.rt7.503.el8_10
linux-kvm (Ubuntu package) - addressed in versions 5.4.0.1149.145, 5.4.0-1149.158
linux-oracle-5.4 (Ubuntu package) - update to 5.4.0-1161.171~18.04.1
linux-aws-fips (Ubuntu package) - addressed in versions 5.4.0.1163.110, 5.4.0-1163.174+fips1
linux-gcp-fips (Ubuntu package) - addressed in versions 5.4.0.1165.107, 5.4.0-1165.174+fips1, 6.8.0-1064.72+fips1
linux-azure-5.4 (Ubuntu package) - addressed in versions 5.4.0.1167.103, 5.4.0-1167.173+fips1, 5.4.0-1167.173~18.04.1
bpftool - update to 5.10.0-323.0.0.224
perf-debuginfo - update to 5.10.0-323.0.0.224
bpftool-debuginfo - update to 5.10.0-323.0.0.224
kernel-headers - update to 5.10.0-323.0.0.224
kernel-devel - update to 5.10.0-323.0.0.224
kernel-debugsource - update to 5.10.0-323.0.0.224
kernel-debuginfo - update to 5.10.0-323.0.0.224
kernel-source - update to 5.10.0-323.0.0.224
kernel-tools - update to 5.10.0-323.0.0.224
kernel-tools-debuginfo - update to 5.10.0-323.0.0.224
kernel - update to 5.10.0-323.0.0.224
kernel-tools-devel - update to 5.10.0-323.0.0.224
perf - update to 5.10.0-323.0.0.224
python3-perf-debuginfo - update to 5.10.0-323.0.0.224
python3-perf - update to 5.10.0-323.0.0.224
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-raspi (Ubuntu package) - addressed in versions 5.15.0.1106.104, 5.15.0-1106.109, 6.8.0-1061.65, 6.8.0-2050.52
linux-intel-iotg (Ubuntu package) - addressed in versions 5.15.0.1107.106, 5.15.0-1107.113
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
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-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-nvidia-6.17 (Ubuntu package) - update to 6.17.0-1032.32
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-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

• https://git.kernel.org/stable/c/523762e3b6933fff81f01dfa3c60c0774044cdab
• https://git.kernel.org/stable/c/7df9863bf538a626e8a684e59cb2c43eac0ef3c8
• https://git.kernel.org/stable/c/8cd0358379570003659186706e077929d6930c40
• https://git.kernel.org/stable/c/8cf6809cddcbe301aedfc6b51bcd4944d45795f6
• https://git.kernel.org/stable/c/9c6afcb1c3cbb2c0da65b8515ac14d7273872f84
• https://git.kernel.org/stable/c/9f69c323ae0ab517e595c2cc74e0ae0d9d085611
• https://git.kernel.org/stable/c/b3264c977e79d8a25778d4fd11520f00fea1329c
• https://git.kernel.org/stable/c/ea2ecd29b8f4433e52607192ca91084f95787ca0

• Out-of-bounds read in Linux kernel netfilter
• openEuler 22.03 LTS SP4 update for kernel
• 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
• Ubuntu update for linux-azure
• Ubuntu update for linux
• Ubuntu update for linux
• Ubuntu update for linux-aws-hwe
• Ubuntu update for linux-oracle
• Ubuntu update for linux
• Ubuntu update for linux-raspi
• Ubuntu update for linux-nvidia-bos
• Ubuntu update for linux-nvidia
• Ubuntu update for linux
• Ubuntu update for linux-gcp-5.15
• Ubuntu update for linux-kvm
• Ubuntu update for linux-fips
• Ubuntu update for linux-azure-5.4
• SUSE update for the Linux Kernel
• Ubuntu update for linux-gcp-fips
• Ubuntu update for linux-oracle-5.4
• Ubuntu update for linux-gcp-7.0
• Red Hat Enterprise Linux 8 update for kernel-rt
• Red Hat Enterprise Linux 8 update for kernel
• Ubuntu update for linux-oracle-7.0
• Ubuntu update for linux-azure-7.0
• Ubuntu update for linux-raspi
• Ubuntu update for linux-aws-fips
• Ubuntu update for linux-nvidia-6.17