CVE-2024-26823 is a vulnerability identified in the Linux kernel specifically related to the interrupt controller subsystem for ARM architectures using the GICv3 ITS (Interrupt Translation Service). The issue arose during a refactoring process of the ITS probing mechanism, where the handling of quirks for ACPI-based platforms was inadvertently removed. ACPI (Advanced Configuration and Power Interface) is a firmware interface used by many modern systems for hardware discovery and configuration. The loss of quirk handling means that certain systems, such as HIP07 platforms, lose their GICv4 functionality, which is critical for interrupt management. In some cases, affected systems may fail to boot unless they are configured to boot with Device Tree (DT) instead of ACPI. The root cause is that the enabling of quirks was not properly integrated into the common probing function (its_probe_one()), leading to inconsistent behavior across different firmware implementations. This vulnerability primarily affects Linux kernel versions containing the specified commit hashes before the fix was applied. While no known exploits are currently reported in the wild, the issue can cause system instability or failure to boot on affected hardware platforms, impacting availability and potentially leading to denial of service. The vulnerability does not directly expose confidentiality or integrity risks but affects system reliability and operational continuity on impacted devices.

For European organizations, the impact of CVE-2024-26823 depends largely on their use of ARM-based Linux systems that rely on ACPI firmware interfaces, particularly those using GICv3 ITS for interrupt management. Industries such as telecommunications, embedded systems, IoT deployments, and edge computing that use ARM hardware with Linux kernels could experience system boot failures or loss of interrupt functionality, leading to downtime or degraded performance. This could disrupt critical services, especially in sectors like manufacturing automation, smart infrastructure, and network equipment providers. While the vulnerability does not enable remote code execution or data breaches, the availability impact could be significant for organizations relying on affected hardware for continuous operations. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to operational failures. European organizations with custom or vendor-specific Linux kernel builds on ARM platforms should prioritize assessment and remediation to avoid service interruptions.

To mitigate CVE-2024-26823, organizations should: 1) Identify Linux systems running on ARM architectures that use ACPI firmware and GICv3 ITS interrupt controllers. 2) Verify kernel versions and check for the presence of the fix that restores quirk probing in its_probe_one(). 3) Apply the latest Linux kernel updates or patches that address this vulnerability as soon as they become available from trusted sources or vendors. 4) For systems unable to update immediately, consider configuring the boot process to use Device Tree (DT) instead of ACPI where feasible, as this can circumvent the issue temporarily. 5) Test updated kernels in staging environments to ensure compatibility and stability before deployment. 6) Monitor system logs and boot processes for signs of interrupt controller failures or boot issues. 7) Engage with hardware and Linux distribution vendors for guidance and support on patch availability and deployment strategies. These steps go beyond generic patching advice by emphasizing firmware interface configuration and targeted identification of affected hardware platforms.