CVE-2022-49203 is a vulnerability identified in the Linux kernel's Direct Rendering Manager (DRM) subsystem, specifically within the AMD GPU display driver code. The flaw arises during the GPU reset process on Display Core (DC) streams, where a double free condition occurs. The vulnerability is rooted in the handling of link encoder assignments during the GPU reset sequence. Initially, the current state, which includes valid link encoder assignments, is backed up before committing zero streams internally from the Display Manager (DM) to DC. During the reset, DC clears the link encoder assignments in the current state but not in the backup, which still holds valid assignments. Subsequently, an interface is called post-reset to clear these assignments in the backup, which also releases an extra reference held by the link encoder interface. This results in a double free of the same memory resource, leading to a NULL pointer dereference. Such a memory management error can cause system instability, crashes, or potentially be exploited for arbitrary code execution if an attacker can trigger the GPU reset path. The fix involves ensuring that after the GPU reset, the backup state does not retain the old assignments by copying from the now clean current state using a new interface, thereby preventing the double free. This vulnerability affects specific Linux kernel versions identified by commit hashes, and no known exploits are currently reported in the wild.

For European organizations, the impact of CVE-2022-49203 can be significant, particularly for those relying on Linux-based systems with AMD GPUs in critical infrastructure, data centers, or enterprise environments. The vulnerability can lead to system crashes or denial of service due to the double free and NULL pointer dereference during GPU resets. In scenarios where GPU reset operations are frequent or can be triggered remotely or by unprivileged users, this could be leveraged to disrupt services or potentially escalate privileges if combined with other vulnerabilities. Industries such as finance, telecommunications, research institutions, and government agencies that utilize Linux servers or workstations with AMD GPUs could face operational disruptions. Additionally, embedded systems or edge devices running vulnerable Linux kernels might be affected, impacting IoT deployments and industrial control systems. While no active exploits are known, the presence of this vulnerability in widely used Linux kernels necessitates prompt attention to avoid future exploitation risks.

European organizations should prioritize updating their Linux kernel to the patched versions that address CVE-2022-49203. Since the vulnerability is in the kernel DRM AMD display driver, kernel upgrades or backported patches from trusted Linux distributions (e.g., Debian, Ubuntu, Red Hat, SUSE) should be applied promptly. Organizations should audit their systems to identify those running affected kernel versions and AMD GPU hardware. For environments where immediate patching is challenging, consider implementing monitoring for abnormal GPU reset events or crashes as an early warning. Additionally, restrict unprivileged user access to GPU reset operations and ensure that GPU drivers and related firmware are kept up to date. In virtualized or containerized environments, ensure that GPU passthrough or sharing configurations do not expose the vulnerability to guest systems. Finally, maintain robust incident response plans to quickly address any instability or suspicious activity related to GPU resets.