Use-after-free in Linux kernel - CVE-2026-74581

 

Use-after-free in Linux kernel - CVE-2026-74581

Published: August 24, 2026


Vulnerability identifier: #VU144982
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-2026-74581
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

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

The vulnerability exists due to a use-after-free in fib6_rule_lookup() and fib6_rule_suppress() in the IPv6 routing rules handler when processing suppressed IPv6 route lookups. A local user can trigger route lookups involving a suppressing rule to cause a denial of service.

The issue occurs because a stale dst entry can be returned after the released route remains referenced in the lookup result.


Affected software

Linux kernel
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server 15 SP5
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Micro
Red Hat CodeReady Linux Builder for ARM 64
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
SUSE Linux Enterprise Live Patching
Public Cloud Module
Development Tools Module
Basesystem Module
Legacy Module
openSUSE Leap
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
kpatch-patch-4_18_0-477_161_1 (Red Hat package)
kpatch-patch-6_12_0-211_49_1 (Red Hat package)
kpatch-patch-4_18_0-477_143_1 (Red Hat package)
kpatch-patch-5_14_0-687_10_1 (Red Hat package)
kpatch-patch-6_12_0-211_16_1 (Red Hat package)
kpatch-patch-4_18_0-477_130_1 (Red Hat package)
kpatch-patch-4_18_0-477_120_1 (Red Hat package)
kpatch-patch-4_18_0-477_107_1 (Red Hat package)
kernel-livepatch-5_14_21-150500_55_189-default
kernel-livepatch-5_14_21-150500_55_189-default-debuginfo
kernel-livepatch-SLE15-SP5_Update_45-debugsource
kernel-livepatch-6_4_0-150600_23_135-default
kernel-livepatch-6_4_0-150600_23_135-default-debuginfo
kernel-livepatch-SLE15-SP6_Update_31-debugsource
kernel-livepatch-SLE15-SP7_Update_21-debugsource
kernel-livepatch-6_4_0-150700_53_81-default-debuginfo
kernel-livepatch-6_4_0-150700_53_81-default
kernel (Red Hat package)
kernel-rt (Red Hat package)
dlm-kmp-rt
kernel-source-rt
kernel-devel-rt
kernel-rt-debugsource
kernel-rt
kernel-rt-devel
kernel-rt-livepatch-devel
kernel-rt_debug
kernel-rt-extra-debuginfo
reiserfs-kmp-rt
kselftests-kmp-rt-debuginfo
kernel-rt_debug-debugsource
gfs2-kmp-rt
kernel-rt-vdso
kernel-rt-optional
ocfs2-kmp-rt-debuginfo
kselftests-kmp-rt
ocfs2-kmp-rt
gfs2-kmp-rt-debuginfo
kernel-rt-debuginfo
kernel-rt_debug-debuginfo
kernel-rt_debug-devel
kernel-rt-optional-debuginfo
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt
kernel-syms-rt
cluster-md-kmp-rt-debuginfo
kernel-rt-devel-debuginfo
kernel-rt_debug-vdso-debuginfo
reiserfs-kmp-rt-debuginfo
kernel-rt-vdso-debuginfo
kernel-rt-livepatch
kernel-rt_debug-vdso
kernel-rt-extra
kernel-rt_debug-devel-debuginfo
cluster-md-kmp-64kb-debuginfo
kernel-default-extra
kernel-obs-qa
kernel-default-extra-debuginfo
kselftests-kmp-default-debuginfo
kselftests-kmp-default
kselftests-kmp-64kb-debuginfo
dlm-kmp-64kb
ocfs2-kmp-64kb
kernel-default-optional
reiserfs-kmp-64kb
ocfs2-kmp-64kb-debuginfo
gfs2-kmp-64kb
dlm-kmp-64kb-debuginfo
kselftests-kmp-64kb
cluster-md-kmp-64kb
kernel-64kb-optional-debuginfo
kernel-64kb-extra
kernel-default-optional-debuginfo
kernel-kvmsmall-devel-debuginfo
kernel-kvmsmall-debugsource
kernel-kvmsmall-devel
kernel-kvmsmall-debuginfo
kernel-default-vdso
kernel-kvmsmall-vdso
kernel-default-vdso-debuginfo
kernel-kvmsmall-vdso-debuginfo
kernel-source-vanilla
kernel-docs-html
kernel-kvmsmall
kernel-zfcpdump
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-macros
reiserfs-kmp-default-debuginfo
dlm-kmp-default-debuginfo
kernel-obs-build
ocfs2-kmp-default
cluster-md-kmp-default
kernel-default-debugsource
kernel-default
kernel-source
cluster-md-kmp-default-debuginfo
kernel-devel
kernel-docs
kernel-64kb
kernel-64kb-devel-debuginfo
kernel-64kb-debuginfo
kernel-64kb-debugsource
kernel-default-livepatch
kernel-64kb-devel
gfs2-kmp-default
kernel-default-devel-debuginfo
kernel-default-debuginfo
dlm-kmp-default
kernel-syms
reiserfs-kmp-default
ocfs2-kmp-default-debuginfo
kernel-default-devel
gfs2-kmp-default-debuginfo
kernel-default-livepatch-devel
kernel-64kb-extra-debuginfo
kernel-obs-build-debugsource
kernel-64kb-optional
gfs2-kmp-64kb-debuginfo
reiserfs-kmp-64kb-debuginfo
kernel-default-base-rebuild
kernel-default-base
kernel-debug-debugsource
kernel-debug-devel
kernel-debug-debuginfo
kernel-debug-vdso-debuginfo
kernel-debug-vdso
kernel-debug
kernel-debug-devel-debuginfo
kernel-azure-devel-debuginfo
kernel-azure-debuginfo
kernel-azure-debugsource
kernel-azure-devel
kernel-azure
linux (Debian package)
IBM DataPower Gateway

How to mitigate CVE-2026-74581

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
IBM DataPower Gateway - update to 11.0.0.3
kpatch-patch-4_18_0-477_161_1 (Red Hat package) - update to 1-1.el8_8
kpatch-patch-6_12_0-211_49_1 (Red Hat package) - update to 1-1.el10_2
kpatch-patch-4_18_0-477_143_1 (Red Hat package) - update to 1-8.el8_8
kpatch-patch-5_14_0-687_10_1 (Red Hat package) - update to 1-9.el9_8
kpatch-patch-6_12_0-211_16_1 (Red Hat package) - update to 1-9.el10_2
kpatch-patch-4_18_0-477_130_1 (Red Hat package) - update to 1-12.el8_8
kpatch-patch-4_18_0-477_120_1 (Red Hat package) - update to 1-14.el8_8
kpatch-patch-4_18_0-477_107_1 (Red Hat package) - update to 1-15.el8_8
kernel-livepatch-5_14_21-150500_55_189-default - update to 1-150500.11.5.3
kernel-livepatch-5_14_21-150500_55_189-default-debuginfo - update to 1-150500.11.5.3
kernel-livepatch-SLE15-SP5_Update_45-debugsource - update to 1-150500.11.5.3
kernel-livepatch-6_4_0-150600_23_135-default - 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-SLE15-SP6_Update_31-debugsource - update to 1-150600.13.3.4
kernel-livepatch-SLE15-SP7_Update_21-debugsource - 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-6_4_0-150700_53_81-default - update to 1-150700.15.3.1
kernel (Red Hat package) - addressed in versions 4.18.0-305.202.1.el8_4, 4.18.0-372.209.1.el8_6, 4.18.0-553.159.1.el8_10, 5.14.0-284.189.1.el9_2, 5.14.0-427.147.1.el9_4, 5.14.0-570.136.1.el9_6, 5.14.0-687.42.1.el9_8, 6.12.0-55.102.1.el10_0, 6.12.0-231.20.el10nv, 6.12.0-259.27.el10nv
kernel-rt (Red Hat package) - addressed in versions 4.18.0-553.159.1.rt7.500.el8_10, 5.14.0-284.189.1.rt14.474.el9_2
dlm-kmp-rt - update to 5.14.21-150500.13.161.1
kernel-source-rt - update to 5.14.21-150500.13.161.1
kernel-devel-rt - update to 5.14.21-150500.13.161.1
kernel-rt-debugsource - update to 5.14.21-150500.13.161.1
kernel-rt - update to 5.14.21-150500.13.161.1
kernel-rt-devel - update to 5.14.21-150500.13.161.1
kernel-rt-livepatch-devel - update to 5.14.21-150500.13.161.1
kernel-rt_debug - update to 5.14.21-150500.13.161.1
kernel-rt-extra-debuginfo - update to 5.14.21-150500.13.161.1
reiserfs-kmp-rt - update to 5.14.21-150500.13.161.1
kselftests-kmp-rt-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt_debug-debugsource - update to 5.14.21-150500.13.161.1
gfs2-kmp-rt - update to 5.14.21-150500.13.161.1
kernel-rt-vdso - update to 5.14.21-150500.13.161.1
kernel-rt-optional - update to 5.14.21-150500.13.161.1
ocfs2-kmp-rt-debuginfo - update to 5.14.21-150500.13.161.1
kselftests-kmp-rt - update to 5.14.21-150500.13.161.1
ocfs2-kmp-rt - update to 5.14.21-150500.13.161.1
gfs2-kmp-rt-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt_debug-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt_debug-devel - update to 5.14.21-150500.13.161.1
kernel-rt-optional-debuginfo - update to 5.14.21-150500.13.161.1
dlm-kmp-rt-debuginfo - update to 5.14.21-150500.13.161.1
cluster-md-kmp-rt - update to 5.14.21-150500.13.161.1
kernel-syms-rt - update to 5.14.21-150500.13.161.1
cluster-md-kmp-rt-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt-devel-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt_debug-vdso-debuginfo - update to 5.14.21-150500.13.161.1
reiserfs-kmp-rt-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt-vdso-debuginfo - update to 5.14.21-150500.13.161.1
kernel-rt-livepatch - update to 5.14.21-150500.13.161.1
kernel-rt_debug-vdso - update to 5.14.21-150500.13.161.1
kernel-rt-extra - update to 5.14.21-150500.13.161.1
kernel-rt_debug-devel-debuginfo - update to 5.14.21-150500.13.161.1
cluster-md-kmp-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-extra - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-qa - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-extra-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kselftests-kmp-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kselftests-kmp-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kselftests-kmp-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
dlm-kmp-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
ocfs2-kmp-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-optional - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
reiserfs-kmp-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
ocfs2-kmp-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
gfs2-kmp-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
dlm-kmp-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kselftests-kmp-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
cluster-md-kmp-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-64kb-optional-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-64kb-extra - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-optional-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-devel-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-debugsource - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-devel - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-vdso - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-vdso-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall-vdso-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-source-vanilla - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-docs-html - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-kvmsmall - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-zfcpdump - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-zfcpdump-debugsource - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-macros - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-obs-build - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debugsource - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-source - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
cluster-md-kmp-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-devel - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-docs - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-devel-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-debugsource - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-devel - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
dlm-kmp-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-syms - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
reiserfs-kmp-default - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
ocfs2-kmp-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-devel - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
gfs2-kmp-default-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-default-livepatch-devel - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-extra-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-obs-build-debugsource - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1, 6.4.0-150700.53.81.1
kernel-64kb-optional - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
gfs2-kmp-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
reiserfs-kmp-64kb-debuginfo - addressed in versions 5.14.21-150500.55.189.1, 6.4.0-150600.23.135.1
kernel-default-base-rebuild - addressed in versions 5.14.21-150500.55.189.1.150500.6.87.4, 6.4.0-150600.23.135.1.150600.12.62.4
kernel-default-base - addressed in versions 5.14.21-150500.55.189.1.150500.6.87.4, 6.4.0-150600.23.135.1.150600.12.62.4, 6.4.0-150700.53.81.1.150700.17.45.1
kernel-debug-debugsource - update to 6.4.0-150600.23.135.1
kernel-debug-devel - update to 6.4.0-150600.23.135.1
kernel-debug-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-vdso-debuginfo - update to 6.4.0-150600.23.135.1
kernel-debug-vdso - update to 6.4.0-150600.23.135.1
kernel-debug - update to 6.4.0-150600.23.135.1
kernel-debug-devel-debuginfo - update to 6.4.0-150600.23.135.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.81.1
kernel-azure-debugsource - update to 6.4.0-150700.53.81.1
kernel-azure-devel - update to 6.4.0-150700.53.81.1
kernel-azure - update to 6.4.0-150700.53.81.1
linux (Debian package) - update to 6.12.105-1

External References

Related Security Bulletins