Use-after-free in Linux kernel - CVE-2026-31555
Published: April 25, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper handling of a stale pointer in futex_lock_pi() retry path in kernel/futex/core.c when retrying priority-inheritance futex locking after owner exit handling. A local user can trigger repeated futex_lock_pi() operations to cause a kernel warning and crash.
Affected software
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Micro
SUSE Linux Micro Extras
SUSE Linux Enterprise Live Patching
SUSE Real Time Module
Public Cloud Module
Legacy Module
Development Tools Module
Basesystem Module
Ubuntu
openEuler
kernel-livepatch-6_4_0-150700_7_62-rt-debuginfo
kernel-livepatch-6_4_0-150700_7_62-rt
kernel-livepatch-SLE15-SP7-RT_Update_17-debugsource
kernel-livepatch-6_4_0-150700_53_63-default-debuginfo
kernel-livepatch-6_4_0-150700_53_63-default
kernel-livepatch-SLE15-SP7_Update_17-debugsource
perf-debuginfo
python3-perf-debuginfo
python3-perf
perf
kernel-tools-devel
kernel-tools
kernel-source
kernel
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
kernel-tools-debuginfo
bpftool
bpftool-debuginfo
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-ibm-5.15 (Ubuntu package)
linux-intel-iotg (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-5.15 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux (Debian package)
kernel-default-debugsource
kernel-obs-build
kernel-obs-build-debugsource
kernel-default-devel
kernel-syms
kernel-64kb
kernel-default
kernel-64kb-debugsource
kernel-64kb-devel
kernel-default-devel-debuginfo
kernel-default-debuginfo
kernel-macros
kernel-kvmsmall
kernel-default-livepatch
kernel-kvmsmall-debuginfo
kernel-kvmsmall-debugsource
kernel-default-base
kernel-rt-debugsource
ocfs2-kmp-rt-debuginfo
cluster-md-kmp-rt
kernel-rt-devel
kernel-source-rt
kernel-devel-rt
kernel-rt
dlm-kmp-rt
gfs2-kmp-rt-debuginfo
kernel-rt-debuginfo
dlm-kmp-rt-debuginfo
gfs2-kmp-rt
ocfs2-kmp-rt
kernel-rt-devel-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-syms-rt
kernel-default-livepatch-devel
ocfs2-kmp-default
cluster-md-kmp-default
gfs2-kmp-default-debuginfo
dlm-kmp-default
kernel-zfcpdump-debugsource
kernel-64kb-debuginfo
ocfs2-kmp-default-debuginfo
dlm-kmp-default-debuginfo
gfs2-kmp-default
cluster-md-kmp-default-debuginfo
kernel-64kb-devel-debuginfo
kernel-zfcpdump
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-devel
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure
kernel-docs
kernel-default-extra-debuginfo
kernel-default-extra
kernel-zfcpdump-debuginfo
kernel-extra-modules
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-azure-fde-6.8 (Ubuntu package)
linux-gcp-fips (Ubuntu package)
How to mitigate CVE-2026-31555
kernel-livepatch-6_4_0-150700_7_62-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_62-rt - update to 1-150700.1.3.1
kernel-livepatch-SLE15-SP7-RT_Update_17-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_63-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_63-default - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_17-debugsource - update to 1-150700.15.3.1
perf-debuginfo - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
python3-perf-debuginfo - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
python3-perf - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
perf - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-tools-devel - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-tools - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-source - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-headers - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-devel - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-debugsource - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-debuginfo - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
kernel-tools-debuginfo - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
bpftool - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
bpftool-debuginfo - addressed in versions 5.10.0-314.0.0.217, 6.6.0-145.1.14.152, 6.6.0-145.3.14.145
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
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
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-ibm-5.15 (Ubuntu package) - update to 5.15.0-1106.110~20.04.1
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
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-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 (Debian package) - addressed in versions 6.1.170-1, 6.12.85-1
kernel-default-debugsource - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-obs-build - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-obs-build-debugsource - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-default-devel - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-syms - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-64kb - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-default - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-64kb-debugsource - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-64kb-devel - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-default-devel-debuginfo - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-default-debuginfo - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-macros - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-devel - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-source - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-kvmsmall - update to 6.4.0-48.1
kernel-default-livepatch - addressed in versions 6.4.0-48.1, 6.4.0-150700.53.63.1
kernel-kvmsmall-debuginfo - update to 6.4.0-48.1
kernel-kvmsmall-debugsource - update to 6.4.0-48.1
kernel-default-base - addressed in versions 6.4.0-48.1.21.25, 6.4.0-150700.53.63.1.150700.17.37.1
kernel-rt-debugsource - update to 6.4.0-150700.7.62.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.62.1
kernel-rt-devel - update to 6.4.0-150700.7.62.1
kernel-source-rt - update to 6.4.0-150700.7.62.1
kernel-devel-rt - update to 6.4.0-150700.7.62.1
kernel-rt - update to 6.4.0-150700.7.62.1
dlm-kmp-rt - update to 6.4.0-150700.7.62.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.62.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
gfs2-kmp-rt - update to 6.4.0-150700.7.62.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.62.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.62.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.62.1
kernel-syms-rt - update to 6.4.0-150700.7.62.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.63.1
ocfs2-kmp-default - update to 6.4.0-150700.53.63.1
cluster-md-kmp-default - update to 6.4.0-150700.53.63.1
gfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.63.1
dlm-kmp-default - update to 6.4.0-150700.53.63.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.63.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.63.1
ocfs2-kmp-default-debuginfo - update to 6.4.0-150700.53.63.1
dlm-kmp-default-debuginfo - update to 6.4.0-150700.53.63.1
gfs2-kmp-default - update to 6.4.0-150700.53.63.1
cluster-md-kmp-default-debuginfo - update to 6.4.0-150700.53.63.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.63.1
kernel-zfcpdump - update to 6.4.0-150700.53.63.1
reiserfs-kmp-default - update to 6.4.0-150700.53.63.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.63.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.63.1
kernel-azure-devel - update to 6.4.0-150700.53.63.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.63.1
kernel-azure-debugsource - update to 6.4.0-150700.53.63.1
kernel-azure - update to 6.4.0-150700.53.63.1
kernel-docs - update to 6.4.0-150700.53.63.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.63.1
kernel-default-extra - update to 6.4.0-150700.53.63.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.63.1
kernel-extra-modules - update to 6.6.0-145.3.14.145
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
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
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-gcp-fips (Ubuntu package) - update to 6.8.0-1064.72+fips1
External References
- https://git.kernel.org/stable/c/210d36d892de5195e6766c45519dfb1e65f3eb83
- https://git.kernel.org/stable/c/33095ae3bdde5e5c264d7e88a2f3e7703a26c7aa
- https://git.kernel.org/stable/c/5e8e06bf8909e79b4acd950cf578cfc2f10bbefa
- https://git.kernel.org/stable/c/71112e62807d1925dc3ae6188b11f8cfc85aec23
- https://git.kernel.org/stable/c/7475dfad10a05a5bfadebf5f2499bd61b19ed293
- https://git.kernel.org/stable/c/92e47ad03e03dbb5515bdf06444bf6b1e147310d
- https://git.kernel.org/stable/c/de7c0c04ad868f2cee6671b11c0a6d20421af1da
- https://git.kernel.org/stable/c/e7824ec168d2ac883a213cd1f4d6cc0816002a85
Related Security Bulletins
- Use-after-free in Linux kernel futex
- Debian update for linux
- Debian update for linux
- openEuler 22.03 LTS SP4 update for kernel
- openEuler 24.03 LTS SP3 update for kernel
- openEuler 24.03 LTS SP1 update for kernel
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- SUSE update for the Linux Kernel
- 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-5.15
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-aws
- Ubuntu update for linux-nvidia
- 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-azure-fips
- Ubuntu update for linux-intel-iot-realtime
- Ubuntu update for linux-intel-iotg