Improper input validation in Linux kernel - CVE-2026-80551

Vulnerability identifier: #VU145940

CSH Severity: Low

CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-80551

CWE-ID: CWE-20

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to execute arbitrary code or cause a denial of service.

The vulnerability exists due to improper input validation in the vfio_ccw channel program IDAW handling when reading the first IDAW and then processing the full IDAL. A remote attacker can trigger inconsistent IDAW reads to execute arbitrary code or cause a denial of service.

The issue affects the s390 vfio_ccw subsystem and arises because the first IDAW is read separately from the full IDAL.

Linux kernel
openEuler
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (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-nvidia-tegra (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
python3-perf-debuginfo - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
python3-perf - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
perf-debuginfo - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
perf - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-tools-devel - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-tools-debuginfo - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-tools - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-source - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-headers - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-devel - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-debugsource - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-debuginfo - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
bpftool-debuginfo - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
bpftool - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel - addressed in versions 5.10.0-337.0.0.238, 6.6.0-145.3.31.162
kernel-extra-modules - update to 6.6.0-145.3.31.162
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1036.39+1

• https://git.kernel.org/stable/c/08ef2a82115690d6e229615872ac1731af732497
• https://git.kernel.org/stable/c/0d46c2565f173bcddcdcaf44a4f69789a20535e2
• https://git.kernel.org/stable/c/565bef268d75bf7df665bce6923a88cd0eb74592
• https://git.kernel.org/stable/c/fc59e9482117ebdccd6dc7fa8082f8b980fd021e

• Improper input validation in Linux kernel s390 cio driver
• openEuler 24.03 LTS SP3 update for kernel
• Ubuntu update for linux-nvidia-tegra
• openEuler 22.03 LTS SP4 update for kernel
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more