CVE-2024-46747 is a vulnerability identified in the Linux kernel's Human Interface Device (HID) subsystem, specifically affecting the cougar_report_fixup function used for the Cougar 500k Gaming Keyboard. The flaw arises because the function does not properly verify the size of the report descriptor before accessing it, leading to a slab-out-of-bounds read. This means that when the kernel processes input reports from the Cougar 500k keyboard, it may read memory beyond the allocated buffer, potentially causing information leakage or kernel memory corruption. The vulnerability is rooted in insufficient input validation in the HID driver code, which can be triggered by connecting or interacting with the affected keyboard. Although no known exploits are currently reported in the wild, the flaw could be leveraged by an attacker with local access to the system who can connect the vulnerable device or emulate it. The issue affects Linux kernel versions identified by the commit hash 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and similar builds. The vulnerability has been addressed by patching the driver to ensure proper bounds checking before accessing the report descriptor, thereby preventing out-of-bounds reads. This fix is critical for maintaining kernel stability and preventing potential privilege escalation or denial-of-service conditions caused by memory corruption.

For European organizations, this vulnerability poses a moderate risk primarily to systems running Linux kernels with the affected HID driver and that use Cougar 500k Gaming Keyboards or compatible devices. The impact includes potential kernel memory corruption, which could lead to system crashes (denial of service) or, in worst cases, privilege escalation if combined with other vulnerabilities. Organizations with Linux-based infrastructure, especially those in sectors with high usage of specialized input devices (e.g., gaming, multimedia production, or certain industrial control environments), may be more exposed. Since exploitation requires local access and physical or emulated connection of the vulnerable device, remote exploitation risk is low. However, insider threats or compromised endpoints could exploit this to disrupt operations or gain elevated privileges. The vulnerability could affect confidentiality if kernel memory contents are leaked due to out-of-bounds reads. Integrity and availability are also at risk due to potential kernel crashes. Given the widespread use of Linux in European enterprises, public institutions, and critical infrastructure, unpatched systems could face operational disruptions and security risks.

European organizations should prioritize updating their Linux kernels to the latest patched versions that include the fix for CVE-2024-46747. Specifically, they should: 1) Identify all Linux systems using the affected kernel versions and verify if the HID driver for Cougar 500k keyboards is present or in use. 2) Apply official kernel patches or upgrade to kernel versions released after the patch commit to ensure the vulnerability is remediated. 3) Restrict physical access to critical Linux systems to prevent unauthorized connection of malicious or vulnerable HID devices. 4) Implement device whitelisting or USB device control policies to limit the use of unapproved peripherals. 5) Monitor system logs for unusual HID device activity or kernel errors that may indicate exploitation attempts. 6) For environments where patching is delayed, consider disabling the cougar HID driver module if the device is not in use, to reduce attack surface. 7) Educate IT staff about the risks of connecting untrusted input devices to Linux systems. These steps go beyond generic advice by focusing on device control and kernel patch management tailored to this specific vulnerability.