CVE-2024-35835 is a medium-severity vulnerability identified in the Linux kernel, specifically within the Mellanox mlx5 Ethernet driver code (net/mlx5e). The flaw arises from a double-free memory error in the function arfs_create_groups. When memory allocation via kvzalloc fails during the creation of ARFS (Accelerated Receive Flow Steering) groups, the function arfs_create_groups frees a pointer ft->g and returns an error. However, the caller function arfs_create_table, which invokes arfs_create_groups, does not properly handle this error and subsequently calls mlx5e_destroy_flow_table, which attempts to free the same pointer ft->g again. This results in a double-free condition. Double-free vulnerabilities can lead to undefined behavior including memory corruption, which attackers might exploit to cause denial of service or potentially execute arbitrary code. However, this particular vulnerability has a CVSS score of 5.3 (medium severity), with the vector indicating network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), limited confidentiality impact (C:L), no integrity or availability impact (I:N/A:N). This suggests that exploitation can be performed remotely without authentication or user interaction but primarily impacts confidentiality, likely through memory corruption that could leak sensitive information. The vulnerability affects specific Linux kernel versions identified by commit hashes, indicating it is present in certain recent kernel builds. No known exploits are reported in the wild at this time. The flaw is technical and specific to the Mellanox mlx5 Ethernet driver, which is used in high-performance networking environments, often in data centers and enterprise servers running Linux. The issue has been resolved in updated kernel versions, though patch links are not provided in the data.

For European organizations, the impact of CVE-2024-35835 depends largely on their use of Linux systems with Mellanox mlx5 network drivers. Many enterprises, cloud providers, and research institutions in Europe rely on Linux servers for critical infrastructure, including high-speed networking hardware. Exploitation could allow remote attackers to cause memory corruption, potentially leading to information leakage or denial of service on affected systems. While the vulnerability does not directly allow privilege escalation or integrity compromise, the confidentiality impact could expose sensitive data traversing the network interfaces. This is particularly relevant for sectors handling sensitive or regulated data such as finance, healthcare, telecommunications, and government agencies. Additionally, disruption of network interfaces could degrade service availability. Given the medium severity and no known exploits, the immediate risk is moderate, but organizations with exposed Linux servers using affected drivers should prioritize patching to prevent potential exploitation. The vulnerability could also be leveraged as part of a multi-stage attack chain if combined with other vulnerabilities.

European organizations should take the following specific mitigation steps: 1) Identify Linux systems running kernels with the affected mlx5e driver versions by checking kernel version and driver module details. 2) Apply the latest Linux kernel patches or updates that address CVE-2024-35835 as soon as they become available from trusted Linux distributions or kernel maintainers. 3) If immediate patching is not feasible, consider disabling or unloading the mlx5e driver temporarily if it does not impact critical operations, or isolate affected systems from untrusted networks to reduce exposure. 4) Monitor network traffic and system logs for unusual behavior or crashes related to the mlx5e driver that could indicate attempted exploitation. 5) Employ network segmentation and firewall rules to limit external access to vulnerable systems. 6) Engage with hardware vendors and Linux distribution maintainers to obtain timely updates and verify the integrity of patches. 7) Incorporate this vulnerability into vulnerability management and incident response plans to ensure rapid detection and remediation. These steps go beyond generic advice by focusing on driver-specific identification, temporary mitigation via driver management, and proactive monitoring tailored to the nature of the vulnerability.