Vulnerability · Published Sep 16, 2026 · Assigned by Linux
CVE-2026-89920KVM: s390: Fix memory corruption by not reinjecting CK machine checks
High 7.8
In plain English
A high-severity security flaw in Linux from Linux. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
In the Linux kernel, the following vulnerability has been resolved: KVM: s390: Fix memory corruption by not reinjecting CK machine checks Channel-subsystem damage machine checks are for the host channel subsystem. The guest channel subsystem is emulated in the userspace VMM. There is no point in forwarding such machine checks into the guest. This also simplifies the machine check reinjection and avoids kfree of a stack variable as reported by sashiko. There might be still machine checks that have the ck bit set with another bit (like instruction damage), mask out the CK bit in s390_backup_mcck_info(), like the CP and ED bits already are.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | linux | no fix listed | DEBIAN-CVE-2026-89920 |
| Debian:13 | linux | 6.12.115-2 | DEBIAN-CVE-2026-89920 |
| Debian:14 | linux | 7.2.6-1 | DEBIAN-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux | 7.0.0-42.42 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-allwinner-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-aws | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-aws | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-aws | 7.0.0-1016.17 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-aws-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-aws-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-aws-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-aws-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-aws-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-aws-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-aws-7.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-azure | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-6.11 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-7.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-azure-fde | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-fde-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-fde-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-azure-fde-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-fde-7.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-nvidia | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-azure-nvidia-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gcp | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gcp | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-gcp | 7.0.0-1016.18 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gcp-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gcp-6.11 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gcp-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gcp-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gcp-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gcp-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gcp-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gcp-7.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gke | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gke | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-gke | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-gkeop | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-gkeop | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-hwe-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-hwe-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-hwe-7.0 | 7.0.0-42.42~24.04.1 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-ibm | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-ibm | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-ibm | 7.0.0-1017.17 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-ibm-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-intel-iotg | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-kvm | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-lowlatency | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-lowlatency | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-lowlatency-hwe-6.11 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-lowlatency-hwe-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-nvidia | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-nvidia-6.11 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-nvidia-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-nvidia-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-nvidia-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-nvidia-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-nvidia-7.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-nvidia-bos | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-nvidia-lowlatency | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-nvidia-tegra | 6.8.0-1038.42 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-nvidia-tegra-igx | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oem-5.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oem-6.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oem-6.1 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oem-6.11 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oem-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oem-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oem-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oem-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-oem-7.0 | 7.0.0-1017.17 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oracle | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oracle | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-oracle | 7.0.0-1015.16 | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oracle-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oracle-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oracle-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-oracle-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-oracle-7.0 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-raspi | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-riscv | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:26.04:LTS | linux-riscv | 7.0.0-42.42.1 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-riscv-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-riscv-6.14 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-riscv-6.17 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-riscv-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-riscv-6.8 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-riscv-7.0 | 7.0.0-42.42.1~24.04.1 | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-starfive-5.19 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-starfive-6.2 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-starfive-6.5 | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-vmware | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:24.04:LTS | linux-xilinx | no fix listed | UBUNTU-CVE-2026-89920 |
| Ubuntu:22.04:LTS | linux-xilinx-zynqmp | no fix listed | UBUNTU-CVE-2026-89920 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | 4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – before 045f3e95a0deccb277c29bd003e1d43c0ad40c904d62fcc0b692e3b4058d7d138114c27cd8b011f7 – before 5c63e2ed840c85e27172ab78e7db3ac77fba281b4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – before b7631982fb65dd355acd18e62b384bc8125e9c444d62fcc0b692e3b4058d7d138114c27cd8b011f7 – before 6ee52d3af2a1bf70349cf3f860933c8d221e229a4d62fcc0b692e3b4058d7d138114c27cd8b011f7 – before 7077ec953996acc04b49d1dfc43df1c1a2a743954d62fcc0b692e3b4058d7d138114c27cd8b011f7 – before 546dde823a36d7283dcf46127c2f3d093443860f |
| Linux | Linux | 4.13 |
References
- https://git.kernel.org/stable/c/045f3e95a0deccb277c29bd003e1d43c0ad40c90
- https://git.kernel.org/stable/c/5c63e2ed840c85e27172ab78e7db3ac77fba281b
- https://git.kernel.org/stable/c/b7631982fb65dd355acd18e62b384bc8125e9c44
- https://git.kernel.org/stable/c/6ee52d3af2a1bf70349cf3f860933c8d221e229a
- https://git.kernel.org/stable/c/7077ec953996acc04b49d1dfc43df1c1a2a74395
- https://git.kernel.org/stable/c/546dde823a36d7283dcf46127c2f3d093443860f