Always-Incorrect Control Flow Implementation in Linux kernel - CVE-2026-43331

 

Always-Incorrect Control Flow Implementation in Linux kernel - CVE-2026-43331

Published: May 9, 2026


Vulnerability identifier: #VU130856
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-2026-43331
CWE-ID: CWE-670
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 improper handling of kcOV instrumentation state in machine kexec code when executing kexec on a KCOV-instrumented kernel. A local user can trigger a kexec operation to cause a denial of service.

Exploitation requires CONFIG_KEXEC and CONFIG_KCOV to be enabled simultaneously, and the issue is not relevant to 32-bit kernels.


Affected software

Linux kernel
Debian Linux
Ubuntu
openEuler
linux (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-realtime (Ubuntu package)
linux-lowlatency-hwe-6.8 (Ubuntu package)
linux-fips (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-azure-6.8 (Ubuntu package)
linux-nvidia-lowlatency (Ubuntu package)
linux-gkeop (Ubuntu package)
linux-nvidia-6.8 (Ubuntu package)
linux-gke (Ubuntu package)
linux-ibm-6.8 (Ubuntu package)
linux-gcp-6.8 (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-gcp-fips (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-realtime-6.8 (Ubuntu package)
python3-perf-debuginfo
python3-perf
perf-debuginfo
perf
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool-debuginfo
bpftool
kernel
kernel-extra-modules
linux (Debian package)

How to mitigate CVE-2026-43331

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 6.8.0-146.146
linux-lowlatency (Ubuntu package) - update to 6.8.0-146.146.1
linux-gcp (Ubuntu package) - update to 6.8.0-1070.78
linux-azure (Ubuntu package) - update to 6.8.0-1070.78
linux-aws (Ubuntu package) - update to 6.8.0-1066.69
linux-ibm (Ubuntu package) - update to 6.8.0-1066.67
linux-oracle (Ubuntu package) - update to 6.8.0-1063.66
linux-azure-fde (Ubuntu package) - update to 6.8.0-1068.75
linux-nvidia (Ubuntu package) - update to 6.8.0-1064.67
linux-realtime (Ubuntu package) - update to 6.8.1-1061.62
linux-lowlatency-hwe-6.8 (Ubuntu package) - update to 6.8.0-146.146.1~22.04.1
linux-fips (Ubuntu package) - update to 6.8.0-146.146+fips1
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1068.75~22.04.1
linux-aws-6.8 (Ubuntu package) - update to 6.8.0-1066.69~22.04.1
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1038.42
linux-azure-6.8 (Ubuntu package) - update to 6.8.0-1070.78~22.04.1
linux-nvidia-lowlatency (Ubuntu package) - update to 6.8.0-1064.67.1
linux-gkeop (Ubuntu package) - update to 6.8.0-1051.55
linux-nvidia-6.8 (Ubuntu package) - update to 6.8.0-1064.67~22.04.1
linux-gke (Ubuntu package) - update to 6.8.0-1065.73
linux-ibm-6.8 (Ubuntu package) - update to 6.8.0-1066.67~22.04.1
linux-gcp-6.8 (Ubuntu package) - update to 6.8.0-1070.78~22.04.1
linux-aws-fips (Ubuntu package) - update to 6.8.0-1066.69+fips1
linux-gcp-fips (Ubuntu package) - update to 6.8.0-1070.78+fips1
linux-azure-fips (Ubuntu package) - update to 6.8.0-1069.77+fips1
linux-realtime-6.8 (Ubuntu package) - update to 6.8.1-1061.62~22.04.1
python3-perf-debuginfo - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
python3-perf - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
perf-debuginfo - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
perf - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-tools-devel - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-tools - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-source - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-headers - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-devel - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-debugsource - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-debuginfo - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
bpftool-debuginfo - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
bpftool - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel - addressed in versions 6.6.0-145.1.22.159, 6.6.0-145.3.26.157
kernel-extra-modules - update to 6.6.0-145.3.26.157
linux (Debian package) - update to 6.12.94-1

External References

Related Security Bulletins