CVE-2023-52571 is a high-severity vulnerability identified in the Linux kernel, specifically within the power supply driver for the rk817 chip. The issue stems from a reference count leak in the driver's probe function. Reference counting is a critical memory management technique used to track resource usage and ensure proper cleanup. In this case, the function of_node_put(), which decrements the reference count of device tree nodes, was not consistently called on all error return paths and during driver removal. This oversight leads to a refcount leak, meaning that the reference count is not properly decremented, causing the kernel to hold onto resources longer than necessary. Over time, this can result in resource exhaustion, potentially leading to denial of service (DoS) conditions due to memory leaks or system instability. The vulnerability requires local access with low privileges (PR:L) and does not require user interaction (UI:N). The attack vector is local (AV:L), meaning an attacker must have some level of access to the system to exploit it. The CVSS v3.1 score is 7.1, indicating a high severity, with high impact on confidentiality and availability but no impact on integrity. Although no known exploits are currently reported in the wild, the flaw's nature suggests that persistent exploitation could degrade system performance or cause crashes. The vulnerability affects specific Linux kernel versions identified by commit hashes, indicating it is present in certain kernel builds prior to the fix. The issue was discovered through static analysis using the Smatch tool, highlighting the importance of rigorous code review in kernel development. The fix involves ensuring that of_node_put() is called on all error return paths and during driver removal to properly manage reference counts and prevent leaks.

For European organizations, this vulnerability poses a risk primarily to systems running affected Linux kernel versions with the rk817 power supply driver in use. The impact includes potential denial of service due to resource exhaustion or system instability caused by the reference count leak. This could affect critical infrastructure, industrial control systems, embedded devices, or servers that rely on this kernel component. Confidentiality impact is rated high in the CVSS, which may indicate that the leak could indirectly expose sensitive information through system crashes or memory mismanagement, although the primary concern is availability. Organizations with Linux-based environments, especially those deploying custom or embedded Linux kernels in IoT devices, telecommunications equipment, or specialized hardware using rk817, may face operational disruptions. Given the local attack vector, the threat is more relevant to insider threats or attackers who have gained limited access to the system. The absence of known exploits in the wild reduces immediate risk but does not eliminate the need for prompt remediation. European entities in sectors such as manufacturing, energy, and telecommunications, which often use embedded Linux systems, should be particularly vigilant. Additionally, the vulnerability could be leveraged in multi-tenant environments or cloud infrastructures where local access is possible, potentially impacting service availability.

To mitigate CVE-2023-52571, European organizations should: 1) Identify and inventory Linux systems running kernel versions containing the vulnerable rk817 power supply driver. 2) Apply the official Linux kernel patches that fix the reference count leak as soon as they become available, or upgrade to a kernel version where the issue is resolved. 3) For embedded or custom Linux distributions, ensure that kernel builds incorporate the fix and conduct thorough testing to confirm the absence of refcount leaks. 4) Implement strict access controls to limit local user privileges, reducing the risk of exploitation by unauthorized users. 5) Monitor system logs and resource usage metrics for signs of memory leaks or unusual resource consumption that could indicate exploitation attempts. 6) Employ runtime integrity monitoring tools to detect abnormal kernel behavior or crashes. 7) Educate system administrators and security teams about the vulnerability and the importance of timely patching, especially in environments with embedded Linux devices. 8) Consider network segmentation and isolation of critical Linux-based systems to limit lateral movement in case of compromise. These steps go beyond generic advice by focusing on kernel patch management, access control, and monitoring tailored to the nature of this vulnerability.