CVE-2022-43750 is a vulnerability in the usbmon subsystem of the Linux kernel, specifically in the file drivers/usb/mon/mon_bin.c. This vulnerability exists in Linux kernel versions prior to 5.19.15 and 6.x versions before 6.0.1. Usbmon is a kernel component that provides monitoring of USB traffic to user-space clients. The flaw allows a user-space client with high privileges (PR:H) to corrupt the internal memory of the usbmon monitor. The vulnerability is classified as CWE-787, which corresponds to out-of-bounds write errors. This means that a malicious or buggy user-space client can write data beyond the allocated buffer boundaries within the usbmon kernel module, leading to memory corruption. The CVSS v3.1 base score is 6.7, indicating a medium severity level. The vector string (AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H) shows that the attack requires local access (AV:L), low attack complexity (AC:L), and high privileges (PR:H). No user interaction is needed (UI:N), and the scope is unchanged (S:U). The impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H), meaning that exploitation could lead to full compromise of the kernel memory related to usbmon, potentially allowing privilege escalation, denial of service, or information disclosure. There are no known exploits in the wild at the time of publication, and no patch links were provided in the source data, but the vulnerability was fixed in Linux kernel versions 5.19.15 and 6.0.1 and later. This vulnerability is relevant to any Linux system using affected kernel versions with usbmon enabled and accessible by privileged user-space clients.

For European organizations, this vulnerability poses a significant risk primarily to servers, workstations, and embedded devices running vulnerable Linux kernel versions with usbmon enabled. Since exploitation requires high privileges, the main risk vector is from insider threats or attackers who have already gained elevated access. Successful exploitation could lead to kernel memory corruption, potentially resulting in privilege escalation, system crashes, or data leakage. This could disrupt critical services, especially in sectors relying heavily on Linux infrastructure such as telecommunications, finance, government, and industrial control systems. The vulnerability could also be leveraged as part of a multi-stage attack to gain persistent kernel-level control. Given the widespread use of Linux in European data centers and embedded systems, the impact could be broad if patches are not applied promptly. However, the requirement for local high privileges limits remote exploitation risks, reducing the likelihood of large-scale automated attacks. Still, targeted attacks against high-value assets remain a concern.

European organizations should take the following specific actions: 1) Identify all Linux systems running kernel versions prior to 5.19.15 or 6.0.1, especially those with usbmon enabled or accessible to user-space clients. 2) Apply kernel updates to versions 5.19.15, 6.0.1, or later as soon as possible to remediate the vulnerability. 3) Restrict access to usbmon interfaces to trusted users only, minimizing the number of users with high privileges who can interact with usbmon. 4) Implement strict privilege management and monitoring to detect any unauthorized attempts to access or manipulate usbmon. 5) Employ kernel integrity monitoring tools to detect abnormal kernel memory corruption or crashes that could indicate exploitation attempts. 6) For embedded or specialized Linux devices where kernel updates may be delayed, consider disabling usbmon if it is not required for operational purposes. 7) Conduct regular security audits and vulnerability scans to ensure no vulnerable kernels remain in production environments. These targeted mitigations go beyond generic patching advice by emphasizing access control and monitoring specific to usbmon usage.