4.7Medium

Linux Linux Kernel

CVE-2026-64373

In the Linux kernel, the following vulnerability has been resolved: cpufreq: Fix hotplug-suspend race during reboot During system reboot, cpufreq_suspend() is called via the kernel_restart() -> device_shutdown() path. Unlike the normal system suspend path, the reboot path does not call freeze_processes(), so userspace processes and kernel threads remain active. This allows CPU hotplug operations to run concurrently with cpufreq_suspend(). The original code has no synchronization with CPU hotplug, leading to a race condition where governor_data can be freed by the hotplug path while cpufreq_suspend() is still accessing it, resulting in a null pointer dereference: Unable to handle kernel NULL pointer dereference Call Trace: do_kernel_fault+0x28/0x3c cpufreq_suspend+0xdc/0x160 device_shutdown+0x18/0x200 kernel_restart+0x40/0x80 arm64_sys_reboot+0x1b0/0x200 Fix this by adding cpus_read_lock()/cpus_read_unlock() to cpufreq_suspend() to block CPU hotplug operations while suspend is in progress. [ rjw: Changelog edits ]

What this means for your business

  • It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it only with access to the machine itself, with an ordinary user login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a less than 0.1% chance of attack attempts being seen in the next 30 days, ranking above 0% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

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Scoring

CVSS
4.7 (v3.1)
Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness
CWE-362
Assigned by
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Dates

Published
2026-07-25
Last modified
2026-09-08
Sources
NVD

Affected products

  • Linux Linux Kernel4.4.198 - 4.5, 4.9.198 - 4.10, 4.14.151 - 4.15, 4.19.81 - 4.20, 5.3.8 - 5.4, 5.4.1 - 5.10.261, 5.11 - 5.15.212, 5.16 - 6.1.178, 6.2 - 6.6.145, 6.7 - 6.12.96, 6.13 - 6.18.39, 6.19 - 7.1.4, 5.4

As listed in the NVD configuration data. Not a statement about your estate.

References