Race condition in Linux kernel - CVE-2026-53269

Vulnerability identifier: #VU135473

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-2026-53269

CWE-ID: CWE-362

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to a race condition in the synproxy hook reference counting logic in netfilter when concurrently adding the first iptables target or nftables expression. A local user can trigger concurrent registration or teardown operations to cause a denial of service.

The issue affects on-demand netfilter hook registration performed by the SYNPROXY infrastructure from both iptables and nftables frontends.

Linux kernel
openEuler
bpftool
kernel
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
bpftool - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
python3-perf-debuginfo - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
python3-perf - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
perf-debuginfo - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
perf - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-tools-devel - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-tools-debuginfo - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-tools - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-source - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-headers - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-devel - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-debugsource - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
kernel-debuginfo - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157
bpftool-debuginfo - addressed in versions 5.10.0-323.0.0.224, 6.6.0-145.1.20.157

• https://git.kernel.org/stable/c/0ec9ddc1bda261a2c57636c74c8b4e53000102c9
• https://git.kernel.org/stable/c/0f8ba5e4c53d2e4a536aa68140beda9fe59b2f88
• https://git.kernel.org/stable/c/2fcba19caaeb2a33017459d3430f057967bb91b6
• https://git.kernel.org/stable/c/56ffbe3a08c01dcdb0d6adee9ce1e535bfb3b389
• https://git.kernel.org/stable/c/640441348258220e78daed40528b85b8afcedab6
• https://git.kernel.org/stable/c/aaf80701dc2f7a48fe543961e21f8ca3924d587c
• https://git.kernel.org/stable/c/debc57b83d5b323df74bf010c8d50fe26ad2ed6b
• https://git.kernel.org/stable/c/fbf0591275f50eae5733c3d7a8cd6c1e79933ffa

• Race condition in Linux kernel netfilter
• openEuler 22.03 LTS SP4 update for kernel
• openEuler 24.03 LTS SP1 update for kernel