Race condition in Linux kernel - CVE-2026-72221

 

Race condition in Linux kernel - CVE-2026-72221

Published: August 16, 2026


Vulnerability identifier: #VU143380
CSH Severity: Medium
CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-72221
CWE-ID: CWE-362
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

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

The vulnerability exists due to a race condition in svc_tcp_handshake() in the sunrpc server socket handling code when processing a TLS handshake callback during handshake cancellation. A remote attacker can trigger a TLS handshake timeout or interruption and cause concurrent handshake completion to corrupt the embedded swait_queue or tear down the connection to cause a denial of service.

The issue occurs when cancellation loses the race to handshake completion and the callback is still in flight.


Affected software

Linux kernel
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Micro
SUSE Linux Micro Extras
SUSE Linux Enterprise Live Patching
Basesystem Module
Development Tools Module
SUSE Real Time Module
Legacy Module
Public Cloud Module
openSUSE Leap
openEuler
Ubuntu
kernel-livepatch-SLE15-SP6_Update_31-debugsource
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo
kernel-livepatch-6_4_0-150600_23_135-default
kernel-livepatch-SLE15-SP7-RT_Update_20-debugsource
kernel-livepatch-6_4_0-150700_7_75-rt
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-source
kernel-rt-debuginfo
kernel-rt
kernel-devel-rt
kernel-rt-debugsource
kernel-rt-livepatch
kernel-macros
kernel-source-rt
kernel-kvmsmall
kernel-devel
kernel-default
kernel-64kb
kernel-64kb-debugsource
kernel-64kb-devel
kernel-obs-build
kernel-default-devel
kernel-default-livepatch
kernel-default-debugsource
kernel-syms
kernel-default-debuginfo
kernel-kvmsmall-debugsource
kernel-kvmsmall-debuginfo
kernel-default-devel-debuginfo
kernel-obs-build-debugsource
kernel-default-base
reiserfs-kmp-64kb-debuginfo
kernel-64kb-extra
cluster-md-kmp-64kb-debuginfo
dlm-kmp-64kb
kernel-64kb-extra-debuginfo
ocfs2-kmp-64kb
reiserfs-kmp-default
kselftests-kmp-64kb
cluster-md-kmp-64kb
kernel-64kb-optional-debuginfo
gfs2-kmp-64kb-debuginfo
ocfs2-kmp-64kb-debuginfo
dlm-kmp-64kb-debuginfo
kernel-64kb-debuginfo
gfs2-kmp-64kb
kernel-64kb-devel-debuginfo
reiserfs-kmp-64kb
kernel-default-livepatch-devel
kernel-docs
kselftests-kmp-64kb-debuginfo
kernel-kvmsmall-vdso-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-zfcpdump
kernel-source-vanilla
kernel-docs-html
kernel-kvmsmall-devel-debuginfo
kernel-kvmsmall-devel
kernel-debug-vdso
kernel-default-vdso-debuginfo
kernel-default-vdso
kernel-kvmsmall-vdso
kernel-debug-vdso-debuginfo
kernel-64kb-optional
kernel-debug-debuginfo
kernel-debug-devel
kernel-debug-debugsource
kernel-debug-devel-debuginfo
kernel-debug
kernel-default-extra-debuginfo
kernel-obs-qa
kernel-default-optional-debuginfo
kselftests-kmp-default-debuginfo
kernel-default-extra
kernel-default-optional
kselftests-kmp-default
cluster-md-kmp-default
ocfs2-kmp-default
cluster-md-kmp-default-debuginfo
gfs2-kmp-default
ocfs2-kmp-default-debuginfo
dlm-kmp-default-debuginfo
reiserfs-kmp-default-debuginfo
dlm-kmp-default
gfs2-kmp-default-debuginfo
kernel-default-base-rebuild
kernel-rt-devel-debuginfo
cluster-md-kmp-rt
kernel-rt-devel
dlm-kmp-rt
gfs2-kmp-rt-debuginfo
ocfs2-kmp-rt
gfs2-kmp-rt
ocfs2-kmp-rt-debuginfo
kernel-syms-rt
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-azure
kernel-azure-devel
kernel-azure-debugsource
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-debugsource
kernel-headers
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
python3-perf-debuginfo
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
python3-perf
kernel-extra-modules
linux-nvidia-tegra (Ubuntu package)
linux (Ubuntu package)
linux-gke (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-azure (Ubuntu package)

How to mitigate CVE-2026-72221

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-livepatch-SLE15-SP6_Update_31-debugsource - update to 1-150600.13.3.4
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo - update to 1-150600.13.3.4
kernel-livepatch-6_4_0-150600_23_135-default - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP7-RT_Update_20-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_75-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_75-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_81-default - 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-SLE15-SP7_Update_21-debugsource - update to 1-150700.15.3.1
kernel-source - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-rt-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-rt - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-devel-rt - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-rt-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-rt-livepatch - update to 6.4.0-52.1
kernel-macros - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source-rt - addressed in versions 6.4.0-52.1, 6.4.0-150700.7.75.1
kernel-kvmsmall - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1
kernel-devel - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-devel - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-syms - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-kvmsmall-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1
kernel-default-devel-debuginfo - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-52.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-base - addressed in versions 6.4.0-52.1.21.35, 6.4.0-52.1.21.36, 6.4.0-150600.23.135.1.150600.12.62.4, 6.4.0-150700.53.81.1.150700.17.45.1
reiserfs-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-extra - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
dlm-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-extra-debuginfo - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
reiserfs-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kselftests-kmp-64kb - update to 6.4.0-150600.23.135.1
cluster-md-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-optional-debuginfo - update to 6.4.0-150600.23.135.1
gfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
ocfs2-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
dlm-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-64kb-devel-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-64kb - update to 6.4.0-150600.23.135.1
kernel-default-livepatch-devel - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-docs - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kselftests-kmp-64kb-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-zfcpdump-debugsource - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source-vanilla - update to 6.4.0-150600.23.135.1
kernel-docs-html - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-devel - update to 6.4.0-150600.23.135.1
kernel-debug-vdso - update to 6.4.0-150600.23.135.1
kernel-default-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-vdso - update to 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso - update to 6.4.0-150600.23.135.1
kernel-debug-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-64kb-optional - update to 6.4.0-150600.23.135.1
kernel-debug-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-devel - update to 6.4.0-150600.23.135.1
kernel-debug-debugsource - update to 6.4.0-150600.23.135.1
kernel-debug-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug - update to 6.4.0-150600.23.135.1
kernel-default-extra-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-qa - update to 6.4.0-150600.23.135.1
kernel-default-optional-debuginfo - update to 6.4.0-150600.23.135.1
kselftests-kmp-default-debuginfo - update to 6.4.0-150600.23.135.1
kernel-default-extra - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-optional - update to 6.4.0-150600.23.135.1
kselftests-kmp-default - update to 6.4.0-150600.23.135.1
cluster-md-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - addressed in versions 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-base-rebuild - update to 6.4.0-150600.23.135.1.150600.12.62.4
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.75.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.75.1
kernel-rt-devel - update to 6.4.0-150700.7.75.1
dlm-kmp-rt - update to 6.4.0-150700.7.75.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.75.1
gfs2-kmp-rt - update to 6.4.0-150700.7.75.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
kernel-syms-rt - update to 6.4.0-150700.7.75.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.75.1
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
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-debugsource - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-headers - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-devel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
perf-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
perf - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools-devel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-source - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
python3-perf-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
bpftool-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
bpftool - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
python3-perf - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-extra-modules - update to 6.6.0-145.3.29.160
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1035.38
linux (Ubuntu package) - addressed in versions 7.0.0-34.34~24.04.1, 7.0.0-34.34, 7.0.0-34.34.1, 7.0.0-1012.12~24.04.1, 7.0.0-1013.13~24.04.1, 7.0.0-1013.13, 7.0.0-1014.14, 7.0.0-1020.20
linux-gke (Ubuntu package) - update to 7.0.0-1007.8
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1012.12~24.04.1
linux-gcp (Ubuntu package) - addressed in versions 7.0.0-1013.13~24.04.1, 7.0.0-1013.13, 7.0.0-1014.14
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1017.17

External References

Related Security Bulletins