CVE-2026-90364 ACPI: processor: Unregister cpufreq notifier on init failure
A failure in Linux kernel ACPI processor initialization leaves a cpufreq notifier registered, potentially causing system instability or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90364?
CVE-2026-90364 is a denial of service vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ACPI: processor: Unregister cpufreq notifier on init failure
acpi_processor_driver_init() registers the cpufreq policy notifier before registering the ACPI processor driver and setting up CPU hotplug state.
If driver_register() or cpuhp_setup_state() fails, the error path only unregisters the ACPI processor driver and the idle driver. The cpufreq notifier remains registered even though initialization failed.
Mirror the module exit path on the init failure path and unregister the cpufreq notifier when it has been registered.
Which versions are affected by CVE-2026-90364?
How do I fix CVE-2026-90364?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-90364 being exploited?
There is no known exploitation of CVE-2026-90364 in the wild and no public exploit code.
Sources
Also known as AZL-102984, BELL-CVE-2026-90364, DEBIAN-CVE-2026-90364, GHSA-q82p-xqw2-q8m2, UBUNTU-CVE-2026-90364.