CVE-2026-64227: ACPI: driver: Check ACPI_COMPANION() against NULL during probe

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-24 · updated 2026-08-13
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: ACPI: driver: Check ACPI_COMPANION() against NULL during probe Since every platform driver can be forced to match a device that doesn't match its list of device IDs because of device_match_driver_override(), platform drivers that rely on the existence of a device's ACPI companion object should verify its presence. Accordingly, add requisite ACPI_COMPANION() or ACPI_HANDLE() checks against NULL to 13 platform drivers handling core ACPI devices. Also change the value returned by the ACPI thermal zone driver when the device's ACPI companion is not present to -ENODEV for consistency with the other drivers.

Affected products

Linux kernel: from 6.7 before 6.12.97; from 6.13 before 6.18.40; from 6.19 before 7.0.11; 7.1-rc1, 7.1-rc2, 7.1-rc3 — fixed in 6.12.97, 6.18.40, 7.0.11

How to fix

Upgrade to a fixed version: Linux kernel 6.12.97, 6.18.40, 7.0.11. Check the vendor advisory for mitigations.

References

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