CVE-2022-48856 is a vulnerability identified in the Linux kernel, specifically within the gianfar Ethernet driver component's ethtool interface. The issue arises from a reference count leak in the function gfar_get_ts_info. The root cause is related to improper management of device tree node references: the function of_find_compatible_node() returns a node pointer with an incremented reference count, but the corresponding release function of_node_put() was not called after usage. This omission leads to a reference count leak, which can cause resource exhaustion over time. While this vulnerability does not directly enable code execution or privilege escalation, the leak can degrade system stability and reliability, potentially leading to denial of service (DoS) conditions if the kernel runs out of resources due to unreleased references. The fix involves adding the missing of_node_put() call to properly decrement the reference count and prevent the leak. The vulnerability affects specific Linux kernel versions identified by the commit hash 7349a74ea75ca27606ead81df3ed67f1b32a94ba and similar versions containing the flawed code. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet.

For European organizations, the impact of CVE-2022-48856 is primarily related to system stability and availability. Organizations running Linux systems with the affected kernel versions, especially those utilizing the gianfar Ethernet driver (commonly found in certain embedded or specialized network hardware), may experience gradual degradation of network interface functionality or kernel resource exhaustion. This could lead to intermittent network outages or system crashes, impacting critical infrastructure, data centers, or industrial control systems that rely on continuous Linux-based operations. While the vulnerability does not directly compromise confidentiality or integrity, the resulting denial of service could disrupt business operations, cause downtime, and increase operational costs. The impact is more pronounced in environments with high network traffic or long uptimes where the leak can accumulate. European sectors such as telecommunications, manufacturing, and public services that deploy Linux-based network devices or embedded systems are particularly at risk if patches are not applied promptly.

To mitigate CVE-2022-48856, European organizations should: 1) Identify Linux systems running affected kernel versions, especially those using the gianfar Ethernet driver or similar network drivers. 2) Apply the official Linux kernel patches that include the fix for the missing of_node_put() call as soon as they become available from trusted Linux distributions or kernel maintainers. 3) For embedded or specialized devices where kernel updates are less frequent, coordinate with hardware vendors to obtain firmware or kernel updates addressing this issue. 4) Monitor system logs and network interface statistics for signs of resource leaks or instability that could indicate the vulnerability is impacting operations. 5) Implement proactive system restarts or resource monitoring as a temporary workaround until patches are applied to prevent prolonged resource exhaustion. 6) Maintain an inventory of Linux kernel versions and network drivers in use to facilitate rapid response to similar vulnerabilities in the future.