CVE-2023-53002 is a vulnerability identified in the Linux kernel's Direct Rendering Manager (DRM) subsystem, specifically within the Intel i915 graphics driver component. The issue stems from improper handling of memory management related to mmap_offset reuse. The functions drm_vma_node_allow() and drm_vma_node_revoke() are designed to be called in balanced pairs to manage virtual memory areas (VMAs) associated with file mappings. However, the current implementation calls drm_vma_node_allow() once per file every time a user invokes mmap_offset, but drm_vma_node_revoke() only once per file on each mmap_offset. Due to the reuse of mmap_offset by clients, this imbalance causes the per-file vm_count to remain non-zero, leading to a leak in the red-black tree (rbtree) data structure that tracks these VMAs. This memory leak can result in gradual consumption of kernel memory resources, potentially degrading system performance or causing instability over time. The fix involves replacing drm_vma_node_allow() with drm_vma_node_allow_once(), ensuring that the allowance is granted only once per file, thereby preventing the memory leak. This vulnerability does not appear to have known exploits in the wild and lacks a CVSS score, indicating it may be a recently discovered issue with limited public exposure so far.

For European organizations relying on Linux systems with Intel integrated graphics using the i915 driver, this vulnerability could lead to memory leaks in the kernel, which may degrade system performance or cause instability, particularly on systems with heavy graphical workloads or long uptimes. While it does not directly enable privilege escalation or remote code execution, the memory leak could be exploited in a denial-of-service (DoS) scenario by exhausting kernel memory resources, impacting availability. Organizations running critical infrastructure, servers, or embedded devices with Linux kernels affected by this flaw might experience unexpected crashes or degraded service quality. The impact is more pronounced in environments where uptime and stability are critical, such as financial institutions, healthcare providers, and industrial control systems prevalent in Europe. However, since no known exploits exist and exploitation requires specific conditions (reuse of mmap_offset in the i915 driver), the immediate risk is moderate but should not be ignored.

European organizations should promptly apply the official Linux kernel patches that replace drm_vma_node_allow() with drm_vma_node_allow_once() in the i915 driver to prevent the memory leak. System administrators should monitor kernel updates from trusted Linux distributions and prioritize updates for systems using Intel integrated graphics. Additionally, organizations should implement proactive monitoring of kernel memory usage and system stability metrics to detect early signs of memory leaks or resource exhaustion. For environments where patching is delayed, consider limiting or isolating workloads that heavily utilize the i915 driver or mmap_offset functionality. Employing kernel live patching solutions where available can reduce downtime during remediation. Finally, maintain robust backup and recovery procedures to mitigate potential service disruptions caused by system instability.