CVE-2024-53113 is a vulnerability identified in the Linux kernel's memory management subsystem, specifically within the alloc_pages_bulk_noprof() function. The issue arises due to a NULL pointer dereference triggered when a task is migrated between different cpusets in a NUMA (Non-Uniform Memory Access) environment. The root cause is a race condition involving the ac->nodemask and ac->preferred_zoneref pointers. When cpuset is enabled, the nodemask may be concurrently modified during task migration, leading to ac->preferred_zoneref pointing to a NULL zone. Subsequently, the function alloc_pages_bulk_noprof() attempts to access this NULL pointer, causing a kernel NULL pointer dereference. This can result in a kernel crash (kernel panic) or system instability. The vulnerability was addressed by adding explicit NULL pointer checks for preferred_zoneref->zone in the kernel's page allocation code, preventing dereferencing of NULL pointers. The flaw affects Linux kernel versions prior to the patch and is particularly relevant in systems utilizing cpusets and NUMA configurations. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet.

For European organizations, this vulnerability poses a risk primarily to servers and infrastructure running Linux kernels with cpuset and NUMA enabled, which is common in high-performance computing, cloud environments, and enterprise data centers. Exploitation could lead to denial of service through kernel crashes, impacting availability of critical services. While it does not directly lead to privilege escalation or data leakage, the resulting system instability could disrupt operations, cause downtime, and potentially lead to data loss if systems crash unexpectedly. Organizations relying on Linux-based virtualization hosts or container platforms may also be affected, as kernel crashes can impact multiple tenants or services. Given the widespread use of Linux in European public sector, financial institutions, and technology providers, the vulnerability could have significant operational impact if exploited or triggered inadvertently.

Organizations should promptly apply the official Linux kernel patches that address this vulnerability, ensuring that the NULL pointer checks in alloc_pages_bulk_noprof() are in place. For environments where immediate patching is not feasible, consider temporarily disabling cpuset features or restricting task migrations across cpusets and NUMA nodes to reduce exposure. Monitoring kernel logs for signs of NULL pointer dereferences or kernel panics related to memory allocation can help detect attempts to trigger this flaw. Additionally, rigorous testing of kernel updates in staging environments is recommended to validate stability before deployment. Infrastructure teams should also review NUMA and cpuset configurations to ensure they are optimized and do not inadvertently increase risk. Employing kernel live patching solutions where supported can minimize downtime during remediation.