CVE-2024-42119 is a vulnerability identified in the Linux kernel specifically within the Direct Rendering Manager (DRM) subsystem for AMD display drivers. The issue arises from improper handling of an uninitialized or unknown engine identifier (ENGINE_ID_UNKNOWN = -1) when attempting to find free audio resources associated with display engines. The vulnerability manifests as two buffer overrun conditions, where the code erroneously uses the unknown engine ID as an array index, leading to out-of-bounds memory access. This can cause memory corruption, potentially leading to system instability or crashes. The root cause is that the engine ID -1 is used without validation, which is invalid as an array index and indicates an uninitialized state that should not require freeing audio resources. The fix implemented involves skipping the processing for unknown engine IDs and returning NULL instead of proceeding with invalid indexing. This correction eliminates the buffer overrun issues reported by the static analysis tool Coverity. Although no known exploits are currently reported in the wild, the vulnerability affects the Linux kernel's AMD DRM component, which is widely used in systems with AMD graphics hardware. The vulnerability was published on July 30, 2024, and affects multiple versions of the Linux kernel identified by the same commit hash. No CVSS score has been assigned yet, and no specific patch links are provided in the data, but the fix is integrated in the kernel source. The vulnerability does not require user interaction but may require local access to trigger, depending on how the DRM subsystem is accessed and utilized by user-space applications or drivers.

For European organizations, this vulnerability poses a risk primarily to systems running Linux kernels with AMD graphics hardware, especially in environments where graphical processing and audio over HDMI/DisplayPort are utilized. Potential impacts include system crashes or denial of service due to memory corruption, which could disrupt critical services or user productivity. In sectors such as finance, manufacturing, research, and public administration, where Linux is often deployed on workstations and servers, unexpected system instability could lead to operational downtime and data loss. Although there is no evidence of remote exploitation or privilege escalation, local attackers or malicious applications could potentially exploit this flaw to cause denial of service or destabilize systems. This could be leveraged as part of a multi-stage attack or to evade detection by causing system reboots. Given the widespread use of Linux in European data centers, cloud environments, and embedded systems, the vulnerability could have a broad impact if left unpatched. However, the lack of known exploits and the requirement for specific hardware and kernel versions somewhat limit the immediate risk.

European organizations should prioritize updating their Linux kernel to the latest stable version that includes the fix for CVE-2024-42119. Kernel updates should be tested in staging environments to ensure compatibility with existing AMD graphics drivers and applications. System administrators should audit their Linux systems to identify those running affected kernel versions with AMD DRM enabled. For environments where immediate patching is not feasible, consider disabling or restricting access to the DRM subsystem or AMD audio over display features if not required, to reduce attack surface. Monitoring system logs for unusual crashes or memory errors related to the DRM subsystem can help detect exploitation attempts. Additionally, organizations should ensure that local user privileges are tightly controlled to prevent untrusted users from accessing or manipulating the graphics subsystem. Employing kernel hardening techniques and enabling security modules such as SELinux or AppArmor can further mitigate exploitation risks. Finally, maintain awareness of updates from Linux kernel maintainers and AMD regarding this vulnerability and apply patches promptly once available.