Bug 2467129 (CVE-2026-43122)

Summary: CVE-2026-43122 kernel: ACPI: processor: Update cpuidle driver check in __acpi_processor_start()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's Advanced Configuration and Power Interface (ACPI) cpuidle driver. Due to an update in the `__acpi_processor_start()` function, a NULL pointer dereference can occur if `acpi_processor_power_init()` is called without a cpuidle driver. This vulnerability could allow a local attacker to trigger a system crash, leading to a denial of service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-05-06 13:05:51 UTC
In the Linux kernel, the following vulnerability has been resolved:

ACPI: processor: Update cpuidle driver check in __acpi_processor_start()

Commit 7a8c994cbb2d ("ACPI: processor: idle: Optimize ACPI idle
driver registration") moved the ACPI idle driver registration to
acpi_processor_driver_init() and acpi_processor_power_init() does
not register an idle driver any more.

Accordingly, the cpuidle driver check in __acpi_processor_start() needs
to be updated to avoid calling acpi_processor_power_init() without a
cpuidle driver, in which case the registration of the cpuidle device
in that function would lead to a NULL pointer dereference in
__cpuidle_register_device().