CVE-2026-72293

A flaw was found in the kernel's KVM (Kernel-based Virtual Machine) s390 vsie component. A missing radix_tree_preload() call in the _gaccess_shadow_fault() function can prevent the system from guaranteeing forward progress. This could lead to system instability or a Denial of Service (DoS), where the system becomes unresponsive.

A moderate-impact flaw was found in the Linux kernel's KVM support for s390 systems (vsie), which implements nested virtualization on the s390x architecture. The _gaccess_shadow_fault() function was missing a radix_tree_preload() call, which is needed to guarantee forward progress when handling guest shadow page table faults. On an affected kernel, a local attacker able to run a nested virtualization guest could use this flaw to make the system unresponsive, resulting in a denial of service. The vulnerable code was introduced in the upstream kernel in version 7.0 and is not present in the Red Hat Enterprise Linux and Red Hat In-Vehicle OS kernels currently in support; all currently tracked kernel and kernel-rt packages are therefore not affected by this issue.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.