CVE-2022-49717 is a vulnerability identified in the Linux kernel specifically related to the irqchip/apple-aic component. The issue arises from a reference count leak in the function build_fiq_affinity. The root cause is improper management of device tree node references: the function of_find_node_by_phandle() returns a node pointer with its reference count incremented, but the code failed to call of_node_put() to decrement the reference count when the node is no longer needed. This omission leads to a reference count leak, which over time can cause resource exhaustion within the kernel. The vulnerability is a memory management flaw rather than a direct code execution or privilege escalation bug. The leak could degrade system stability or cause denial of service if the kernel runs out of memory or other resources due to unreleased references. The fix involves adding the missing of_node_put() calls to ensure proper reference counting and resource cleanup. The affected versions are identified by specific commit hashes, indicating this is a recent and targeted fix. There are no known exploits in the wild, and no CVSS score has been assigned yet. The vulnerability does not appear to require user interaction or authentication, but exploitation would likely require local access or the ability to trigger the affected kernel code path. Since this is a kernel-level resource leak, it impacts system reliability and availability rather than confidentiality or integrity directly.

For European organizations, the impact of CVE-2022-49717 primarily concerns system stability and availability. Linux is widely used across European enterprises, government agencies, and critical infrastructure, often powering servers, embedded devices, and network equipment. A reference count leak in the kernel could lead to gradual resource depletion, causing system slowdowns, crashes, or reboots. This can disrupt business operations, especially in environments requiring high availability such as financial services, telecommunications, healthcare, and manufacturing. While this vulnerability does not directly expose sensitive data or allow privilege escalation, the resulting denial of service conditions could be exploited by attackers to cause operational disruptions. Organizations relying on Apple hardware running Linux or embedded systems using the apple-aic irqchip driver are particularly at risk. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to potential future attacks or accidental system failures.

To mitigate CVE-2022-49717, European organizations should: 1) Apply the latest Linux kernel updates that include the patch fixing the reference count leak in the irqchip/apple-aic component. 2) Identify systems running affected kernel versions, especially those using Apple hardware or embedded devices with the apple-aic irqchip driver, and prioritize patching. 3) Implement monitoring for kernel resource usage and system stability to detect early signs of resource leaks or degradation. 4) Employ automated patch management processes to ensure timely deployment of kernel updates. 5) For critical systems where immediate patching is not feasible, consider isolating affected devices or limiting access to reduce risk of triggering the vulnerability. 6) Maintain regular backups and disaster recovery plans to minimize impact from potential system outages. 7) Engage with hardware and Linux distribution vendors to confirm patch availability and compatibility.