Improper locking in Linux kernel - CVE-2026-53274
Published: June 26, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a logic flaw in __smc_setsockopt() when copying user-supplied socket option data while holding the socket lock. A local user can pass a userfaultfd-monitored or FUSE-backed memory page as the optval argument to cause a denial of service.
Exploitation can keep the socket lock held indefinitely and, when combined with asynchronous tear-down operations such as shutdown(), can exhaust kernel worker threads and trigger the hung task watchdog.
Affected software
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
Public Cloud Module
Development Tools Module
Basesystem Module
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Legacy Module
Ubuntu
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
ocfs2-kmp-rt
kernel-rt-devel-debuginfo
kernel-rt
kernel-source-rt
kernel-devel-rt
kernel-rt-debuginfo
cluster-md-kmp-rt
kernel-rt-debugsource
ocfs2-kmp-rt-debuginfo
kernel-syms-rt
cluster-md-kmp-rt-debuginfo
gfs2-kmp-rt-debuginfo
kernel-rt-devel
gfs2-kmp-rt
dlm-kmp-rt
dlm-kmp-rt-debuginfo
kernel-docs
kernel-syms
kernel-devel
kernel-macros
kernel-source
kernel-obs-build
kernel-obs-build-debugsource
gfs2-kmp-default
ocfs2-kmp-default-debuginfo
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-default-extra-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
cluster-md-kmp-default
kernel-default-debugsource
kernel-default-debuginfo
kernel-default-devel
kernel-default-devel-debuginfo
kernel-64kb
kernel-64kb-debugsource
kernel-64kb-devel
kernel-64kb-devel-debuginfo
kernel-64kb-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump-debuginfo
kernel-zfcpdump
ocfs2-kmp-default
dlm-kmp-default-debuginfo
cluster-md-kmp-default-debuginfo
dlm-kmp-default
gfs2-kmp-default-debuginfo
kernel-default
kernel-default-base
linux (Ubuntu package)
linux-azure (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-ibm (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-7.0 (Ubuntu package)
linux-raspi (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-53274
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
ocfs2-kmp-rt - update to 6.4.0-150700.7.67.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.67.1
kernel-rt - 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-rt-debuginfo - update to 6.4.0-150700.7.67.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.67.1
kernel-rt-debugsource - update to 6.4.0-150700.7.67.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
kernel-syms-rt - update to 6.4.0-150700.7.67.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
kernel-rt-devel - update to 6.4.0-150700.7.67.1
gfs2-kmp-rt - update to 6.4.0-150700.7.67.1
dlm-kmp-rt - update to 6.4.0-150700.7.67.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.67.1
kernel-docs - update to 6.4.0-150700.53.73.1
kernel-syms - update to 6.4.0-150700.53.73.1
kernel-devel - update to 6.4.0-150700.53.73.1
kernel-macros - update to 6.4.0-150700.53.73.1
kernel-source - update to 6.4.0-150700.53.73.1
kernel-obs-build - update to 6.4.0-150700.53.73.2
kernel-obs-build-debugsource - update to 6.4.0-150700.53.73.2
gfs2-kmp-default - update to 6.4.0-150700.53.73.2
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
reiserfs-kmp-default - update to 6.4.0-150700.53.73.2
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-extra-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
cluster-md-kmp-default - update to 6.4.0-150700.53.73.2
kernel-default-debugsource - update to 6.4.0-150700.53.73.2
kernel-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default-devel - update to 6.4.0-150700.53.73.2
kernel-default-devel-debuginfo - update to 6.4.0-150700.53.73.2
kernel-64kb - update to 6.4.0-150700.53.73.2
kernel-64kb-debugsource - update to 6.4.0-150700.53.73.2
kernel-64kb-devel - update to 6.4.0-150700.53.73.2
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.73.2
kernel-64kb-debuginfo - update to 6.4.0-150700.53.73.2
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.73.2
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.73.2
kernel-zfcpdump - update to 6.4.0-150700.53.73.2
ocfs2-kmp-default - update to 6.4.0-150700.53.73.2
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
dlm-kmp-default - update to 6.4.0-150700.53.73.2
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.73.2
kernel-default - 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 (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1011.11, 7.0.0-1014.14
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13
linux-ibm (Ubuntu package) - update to 7.0.0-1013.13
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia (Ubuntu package) - update to 7.0.0-1018.18
linux-nvidia-7.0 (Ubuntu package) - update to 7.0.0-1018.18~24.04.1
linux-raspi (Ubuntu package) - update to 7.0.0-1019.19
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2018.18
External References
- https://git.kernel.org/stable/c/35a22117839602bb52283de08894c5a7dde92420
- https://git.kernel.org/stable/c/5d27d2ffe487df89ce28fda0410eafa05dbe03a0
- https://git.kernel.org/stable/c/89f6fbe0033c942cb790ffd53ca93a45eeaf1c91
- https://git.kernel.org/stable/c/94d286fa5eedc550d42bcb9c85416af8f77736ff
- https://git.kernel.org/stable/c/a3fdd924d88c30b9f488636ce0e4696012cf5511
- https://git.kernel.org/stable/c/dcd90f42a33e4220385f27b515183d0c91b2fc4a
Related Security Bulletins
- Improper locking in Linux kernel smc
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- Ubuntu update for linux-oem-7.0
- Ubuntu update for linux
- Ubuntu update for linux-gcp-7.0
- Ubuntu update for linux-oracle-7.0
- Ubuntu update for linux-azure
- Ubuntu update for linux-azure-7.0
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-nvidia-bos
- Ubuntu update for linux-ibm
- Ubuntu update for linux-raspi
- Ubuntu update for linux-nvidia-7.0