Improper control of a resource through its lifetime in Linux kernel - CVE-2026-72016
Published: August 16, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state management in cpuhp_smt_enable() and CPU present-mask handling when processing CPU hotplug operations on arm64 ACPI systems with CPUs marked present before registration. A local user can trigger SMT hotplug control on such a system to cause a denial of service.
The issue occurs on arm64 systems booted with ACPI where some CPUs are enumerated as online-capable but are not enabled and have not yet been registered.
Affected software
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-72016
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-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1