CVE-2023-52858 is a medium severity vulnerability identified in the Linux kernel, specifically within the clock management subsystem for MediaTek MT7629 SoCs (System on Chips). The issue arises from the lack of proper validation of the return value from the function mtk_alloc_clk_data(), which is responsible for allocating clock data structures. Without this check, a NULL pointer dereference can occur if the allocation fails. This type of vulnerability is classified under CWE-476 (NULL Pointer Dereference). When the kernel dereferences a NULL pointer, it typically results in a kernel panic or system crash, causing a denial of service (DoS) condition. The CVSS v3.1 base score is 6.2, reflecting a medium severity level. The vector indicates that the attack requires local access (AV:L), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and impacts availability only (A:H) without affecting confidentiality or integrity. There are no known exploits in the wild at the time of publication, and no patch links were provided in the source, but the vulnerability has been resolved by adding the necessary NULL check in the kernel source code. This vulnerability affects specific Linux kernel versions containing the vulnerable code, particularly those running on MediaTek MT7629 hardware platforms. The issue is technical and requires local access to trigger, meaning remote exploitation is unlikely without prior system access.

For European organizations, the primary impact of CVE-2023-52858 is the potential for denial of service on devices running vulnerable Linux kernels on MediaTek MT7629 platforms. This could affect embedded systems, network equipment, or IoT devices using this chipset, leading to system crashes and operational disruptions. While the vulnerability does not compromise confidentiality or integrity, availability interruptions can impact critical infrastructure, industrial control systems, or network devices, especially in sectors relying on embedded Linux systems. Organizations deploying MediaTek MT7629-based devices in telecommunications, manufacturing, or smart city applications may experience service outages or require emergency maintenance. Given the local access requirement, the threat is more relevant to insider threats or attackers who have already gained limited access to the device. The absence of known exploits reduces immediate risk, but unpatched systems remain vulnerable to accidental crashes or targeted DoS attacks by malicious insiders or malware.

To mitigate CVE-2023-52858, European organizations should: 1) Identify all devices and systems running Linux kernels with MediaTek MT7629 clock management code. 2) Apply the latest Linux kernel patches that include the NULL pointer check for mtk_alloc_clk_data(), ensuring the fix is incorporated into all affected kernel versions. 3) For embedded or IoT devices where kernel updates are challenging, coordinate with device vendors or manufacturers to obtain firmware updates or mitigations. 4) Implement strict access controls to limit local access to trusted users only, reducing the risk of exploitation by unauthorized personnel. 5) Monitor system logs and device stability to detect abnormal crashes or kernel panics that may indicate exploitation attempts or accidental triggering of the vulnerability. 6) Incorporate this vulnerability into vulnerability management and patching cycles, prioritizing devices with critical availability requirements. 7) Consider network segmentation and isolation of vulnerable devices to minimize impact in case of a DoS event. These steps go beyond generic advice by focusing on the specific hardware platform and local access nature of the vulnerability.