CVE-2024-53151 is a vulnerability identified in the Linux kernel's svcrdma module, specifically within the Remote Direct Memory Access (RDMA) server-side implementation used by the SunRPC protocol. The flaw arises from an integer overflow condition in the function xdr_check_write_chunk(), located in the file svc_rdma_recvfrom.c. This function processes a user-controlled 32-bit unsigned integer value called 'segcount', which represents the number of segments to be handled. The vulnerability occurs because 'segcount' is multiplied by constants (rpcrdma_segment_maxsz and sizeof(*p)) to calculate the buffer size for decoding incoming data. On 32-bit systems, if 'segcount' is sufficiently large (equal to or exceeding SIZE_MAX / 16), the multiplication results in an integer overflow, causing the computed buffer size to wrap around to a smaller value. Consequently, the subsequent call to xdr_inline_decode() may accept this incorrect size, leading to a potential buffer overflow or memory corruption. This flaw can be exploited by sending specially crafted RDMA requests to vulnerable Linux systems, potentially allowing an attacker to overwrite memory, cause denial of service, or execute arbitrary code. The vulnerability was introduced by commit 78147ca8b4a9 in June 2020 and has been publicly disclosed and patched as of December 2024. No known exploits are currently reported in the wild. The issue primarily affects 32-bit Linux kernel deployments that utilize the svcrdma module for RDMA transport in SunRPC services.

For European organizations, the impact of CVE-2024-53151 can be significant, especially for those relying on Linux servers running 32-bit kernels with RDMA capabilities enabled. RDMA is commonly used in high-performance computing, data centers, and enterprise storage environments to accelerate network communication. Exploitation of this vulnerability could lead to unauthorized code execution, allowing attackers to compromise system confidentiality, integrity, and availability. This could result in data breaches, service disruptions, or lateral movement within corporate networks. Given the critical role of Linux in European public sector, financial institutions, research facilities, and cloud service providers, exploitation could undermine trust and cause operational downtime. Although no active exploits are known, the vulnerability's presence in kernel-level code and the potential for remote exploitation without authentication elevate the risk profile. Organizations using 64-bit kernels are less likely to be affected due to the larger address space mitigating the overflow condition, but mixed environments or legacy systems remain at risk.

European organizations should take the following specific mitigation steps: 1) Immediately identify and inventory Linux systems running 32-bit kernels with svcrdma enabled, focusing on servers providing RPC services over RDMA. 2) Apply the official Linux kernel patches that address CVE-2024-53151 as soon as they become available from trusted Linux distribution vendors or upstream sources. 3) Where patching is delayed, consider disabling the svcrdma module or the RDMA transport for SunRPC services if not strictly required, to reduce the attack surface. 4) Implement network-level controls to restrict access to RDMA ports and services to trusted hosts only, using firewalls and segmentation. 5) Monitor system logs and network traffic for anomalous RDMA requests or unusual segcount values that could indicate exploitation attempts. 6) For critical infrastructure, conduct penetration testing and vulnerability scanning to verify the absence of exploitable conditions. 7) Educate system administrators about this vulnerability and ensure timely application of kernel updates in future maintenance cycles.