CVE-2023-52864 is a vulnerability identified in the Linux kernel, specifically within the platform/x86 subsystem related to the Windows Management Instrumentation (WMI) character device driver. The issue stems from a change introduced in commit fa1f68db6ca7, which modified how the miscdevice structure stores a pointer to itself inside the file's private_data field (filp->private_data). This change means that when the wmi_char_open() function is invoked, private_data is never NULL. However, if the associated WMI device has been deleted (via wmi_free_devices()), wmi_char_open() may fail to find its driver, potentially leading to memory corruption. This occurs because wmi_char_open() might incorrectly reference or pick a wrong WMI device bound to a different driver with the same name as the original, causing invalid memory access. The fix involves using the miscdevice pointer to correctly retrieve the WMI device data associated with the character device using the container_of() macro. This approach prevents wmi_char_open() from mistakenly associating with an incorrect WMI device and thus avoids memory corruption. The vulnerability affects specific Linux kernel versions identified by the commit hash 44b6b7661132b1b0e5fd3147ded66f1e4a817ca9 and was published on May 21, 2024. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet.

For European organizations, this vulnerability poses a risk primarily to systems running affected Linux kernel versions on x86 platforms that utilize WMI character devices. Memory corruption vulnerabilities can lead to system instability, crashes, or potentially allow an attacker to execute arbitrary code with kernel privileges if exploited successfully. This could compromise system confidentiality, integrity, and availability. Given that Linux is widely used in enterprise servers, cloud infrastructure, and embedded systems across Europe, exploitation could disrupt critical services, data processing, and operational technology environments. However, exploitation requires conditions such as the deletion of WMI devices and invocation of wmi_char_open(), which may limit the attack surface. Since no known exploits exist yet, the immediate risk is moderate, but the potential for escalation exists if attackers develop reliable exploitation techniques. Organizations relying on Linux-based infrastructure, especially those in sectors like finance, telecommunications, and government, should consider this vulnerability seriously due to the critical role of Linux in their IT ecosystems.

European organizations should take the following specific mitigation steps: 1) Identify and inventory Linux systems running kernel versions that include the affected commit (44b6b7661132b1b0e5fd3147ded66f1e4a817ca9). 2) Apply the official Linux kernel patches that address CVE-2023-52864 as soon as they become available from trusted sources or Linux distribution vendors. 3) For systems where immediate patching is not feasible, consider disabling or restricting access to WMI character devices if they are not required for operational purposes to reduce attack surface. 4) Monitor system logs and kernel messages for unusual activity related to WMI devices or character device operations that could indicate exploitation attempts. 5) Employ kernel security modules (e.g., SELinux, AppArmor) to enforce strict access controls on device files and limit the ability of unprivileged users or processes to interact with kernel drivers. 6) Maintain robust incident response and forensic capabilities to quickly detect and respond to any signs of exploitation. 7) Engage with Linux distribution security advisories and subscribe to vulnerability notification services to stay informed about updates and exploit developments related to this vulnerability.