Use-after-free in Linux kernel - CVE-2026-74289

 

Use-after-free in Linux kernel - CVE-2026-74289

Published: August 15, 2026


Vulnerability identifier: #VU142903
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-2026-74289
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 fib_leaf_notify() and fib_info reference handling when dumping IPv4 fib_info entries under RCU during fib notifier processing. A local user can trigger network namespace cleanup or device reload operations that invoke affected fib notifier paths to cause a denial of service.

The issue was reported through the netdevsim notifier path, and IPv6 is not affected by the same condition.


Affected software

Linux kernel
SUSE Linux Enterprise Server 12 SP5 LTSS Extended
SUSE Linux Enterprise Server 12 SP5
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 12
SUSE Linux Enterprise Server 12
SUSE Linux Enterprise High Performance Computing 12
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Workstation Extension 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise High Availability Extension 15
SUSE Linux Enterprise Live Patching
Basesystem Module
SUSE Real Time Module
Development Tools Module
Legacy Module
Public Cloud Module
openEuler
Ubuntu
kgraft-patch-4_12_14-122_333-default
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource
kernel-livepatch-6_4_0-150700_7_78-rt
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo
kernel-livepatch-6_4_0-150700_53_84-default
kernel-livepatch-SLE15-SP7_Update_22-debugsource
ocfs2-kmp-default-debuginfo
kernel-default-devel
gfs2-kmp-default-debuginfo
gfs2-kmp-default
kernel-default-devel-debuginfo
kernel-macros
kernel-source
kernel-devel
kernel-default-man
cluster-md-kmp-default-debuginfo
kernel-default-base
kernel-syms
kernel-default-base-debuginfo
cluster-md-kmp-default
ocfs2-kmp-default
dlm-kmp-default-debuginfo
dlm-kmp-default
kernel-default-debuginfo
kernel-default-kgraft-devel
kernel-default-debugsource
kernel-default-kgraft
kernel-default
kernel-rt
gfs2-kmp-rt-debuginfo
kernel-devel-rt
kernel-source-rt
ocfs2-kmp-rt-debuginfo
ocfs2-kmp-rt
gfs2-kmp-rt
dlm-kmp-rt-debuginfo
cluster-md-kmp-rt
kernel-rt-debugsource
kernel-syms-rt
dlm-kmp-rt
kernel-rt-devel
kernel-rt-devel-debuginfo
kernel-rt-debuginfo
cluster-md-kmp-rt-debuginfo
kernel-obs-build-debugsource
reiserfs-kmp-default
reiserfs-kmp-default-debuginfo
kernel-default-livepatch-devel
kernel-default-livepatch
kernel-obs-build
kernel-azure
kernel-azure-debugsource
kernel-azure-devel
kernel-azure-debuginfo
kernel-azure-devel-debuginfo
kernel-default-extra
kernel-default-extra-debuginfo
kernel-docs
kernel-64kb-devel
kernel-64kb-debugsource
kernel-64kb-devel-debuginfo
kernel-64kb-debuginfo
kernel-64kb
kernel-zfcpdump-debuginfo
kernel-zfcpdump-debugsource
kernel-zfcpdump
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-headers
kernel-extra-modules
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
kernel
bpftool
linux-nvidia-tegra (Ubuntu package)
linux (Debian package)
linux-gcp-7.0 (Ubuntu package)
linux (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-azure (Ubuntu package)

How to mitigate CVE-2026-74289

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kgraft-patch-4_12_14-122_333-default - update to 1-8.3.3
kernel-livepatch-SLE15-SP7-RT_Update_21-debugsource - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_78-rt - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_7_78-rt-debuginfo - update to 1-150700.1.3.1
kernel-livepatch-6_4_0-150700_53_84-default-debuginfo - update to 1-150700.15.3.1
kernel-livepatch-6_4_0-150700_53_84-default - update to 1-150700.15.3.1
kernel-livepatch-SLE15-SP7_Update_22-debugsource - update to 1-150700.15.3.1
ocfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
gfs2-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
gfs2-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-devel-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-macros - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-source - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-devel - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-man - update to 4.12.14-122.333.2
cluster-md-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-base - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1.150700.17.47.1
kernel-syms - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-base-debuginfo - update to 4.12.14-122.333.2
cluster-md-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
ocfs2-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
dlm-kmp-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
dlm-kmp-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-debuginfo - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-kgraft-devel - update to 4.12.14-122.333.2
kernel-default-debugsource - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-default-kgraft - update to 4.12.14-122.333.2
kernel-default - addressed in versions 4.12.14-122.333.2, 6.4.0-150700.53.84.1
kernel-rt - update to 6.4.0-150700.7.78.1
gfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
kernel-devel-rt - update to 6.4.0-150700.7.78.1
kernel-source-rt - update to 6.4.0-150700.7.78.1
ocfs2-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
ocfs2-kmp-rt - update to 6.4.0-150700.7.78.1
gfs2-kmp-rt - update to 6.4.0-150700.7.78.1
dlm-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
cluster-md-kmp-rt - update to 6.4.0-150700.7.78.1
kernel-rt-debugsource - update to 6.4.0-150700.7.78.1
kernel-syms-rt - update to 6.4.0-150700.7.78.1
dlm-kmp-rt - update to 6.4.0-150700.7.78.1
kernel-rt-devel - update to 6.4.0-150700.7.78.1
kernel-rt-devel-debuginfo - update to 6.4.0-150700.7.78.1
kernel-rt-debuginfo - update to 6.4.0-150700.7.78.1
cluster-md-kmp-rt-debuginfo - update to 6.4.0-150700.7.78.1
kernel-obs-build-debugsource - update to 6.4.0-150700.53.84.1
reiserfs-kmp-default - update to 6.4.0-150700.53.84.1
reiserfs-kmp-default-debuginfo - update to 6.4.0-150700.53.84.1
kernel-default-livepatch-devel - update to 6.4.0-150700.53.84.1
kernel-default-livepatch - update to 6.4.0-150700.53.84.1
kernel-obs-build - update to 6.4.0-150700.53.84.1
kernel-azure - update to 6.4.0-150700.53.84.1
kernel-azure-debugsource - update to 6.4.0-150700.53.84.1
kernel-azure-devel - update to 6.4.0-150700.53.84.1
kernel-azure-debuginfo - update to 6.4.0-150700.53.84.1
kernel-azure-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-default-extra - update to 6.4.0-150700.53.84.1
kernel-default-extra-debuginfo - update to 6.4.0-150700.53.84.1
kernel-docs - update to 6.4.0-150700.53.84.1
kernel-64kb-devel - update to 6.4.0-150700.53.84.1
kernel-64kb-debugsource - update to 6.4.0-150700.53.84.1
kernel-64kb-devel-debuginfo - update to 6.4.0-150700.53.84.1
kernel-64kb-debuginfo - update to 6.4.0-150700.53.84.1
kernel-64kb - update to 6.4.0-150700.53.84.1
kernel-zfcpdump-debuginfo - update to 6.4.0-150700.53.84.1
kernel-zfcpdump-debugsource - update to 6.4.0-150700.53.84.1
kernel-zfcpdump - update to 6.4.0-150700.53.84.1
python3-perf-debuginfo - update to 6.6.0-145.3.31.162
python3-perf - update to 6.6.0-145.3.31.162
perf-debuginfo - update to 6.6.0-145.3.31.162
perf - update to 6.6.0-145.3.31.162
kernel-tools-devel - update to 6.6.0-145.3.31.162
kernel-tools-debuginfo - update to 6.6.0-145.3.31.162
kernel-tools - update to 6.6.0-145.3.31.162
kernel-source - update to 6.6.0-145.3.31.162
kernel-headers - update to 6.6.0-145.3.31.162
kernel-extra-modules - update to 6.6.0-145.3.31.162
kernel-devel - update to 6.6.0-145.3.31.162
kernel-debugsource - update to 6.6.0-145.3.31.162
kernel-debuginfo - update to 6.6.0-145.3.31.162
bpftool-debuginfo - update to 6.6.0-145.3.31.162
kernel - update to 6.6.0-145.3.31.162
bpftool - update to 6.6.0-145.3.31.162
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1036.39+1
linux (Debian package) - update to 6.12.111-1
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux (Ubuntu package) - addressed in versions 7.0.0-38.38, 7.0.0-38.38.1, 7.0.0-1008.9, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14, 7.0.0-1015.15
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1015.15
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