CVE-2024-35937 is a vulnerability identified in the Linux kernel's WiFi subsystem, specifically within the cfg80211 component responsible for wireless configuration. The issue arises from improper validation of the A-MSDU (Aggregated MAC Service Data Unit) frame format. A-MSDU frames aggregate multiple subframes into a single transmission unit to improve efficiency. The vulnerability occurs when the kernel attempts to parse an A-MSDU frame that appears to contain another subframe, but the header for this subframe is incomplete or malformed. Due to insufficient checks, the kernel may read data beyond the bounds of the actual buffer, leading to an out-of-bounds read. Although the kernel discards the data after reading, this behavior can still lead to information disclosure or potentially trigger undefined behavior, including kernel crashes or memory corruption under certain conditions. The fix involves more rigorous validation to ensure that the subframe header is fully present before any data is read, preventing out-of-bounds access. This vulnerability affects multiple versions of the Linux kernel as indicated by the affected commit hashes, and it was publicly disclosed on May 19, 2024. There are no known exploits in the wild at the time of disclosure, and no CVSS score has been assigned yet. The vulnerability is categorized under the WiFi networking stack, which is a critical component for many Linux-based systems, especially those relying on wireless connectivity.

For European organizations, the impact of CVE-2024-35937 primarily concerns systems running Linux kernels with vulnerable cfg80211 implementations and utilizing WiFi connectivity. Potential impacts include unauthorized information disclosure due to out-of-bounds reads, which could leak sensitive kernel memory contents. While direct remote code execution or privilege escalation is not explicitly indicated, the vulnerability could be leveraged as part of a multi-stage attack chain. Systems with wireless interfaces exposed to untrusted networks (e.g., public WiFi, enterprise guest networks) are at higher risk. This is particularly relevant for sectors such as finance, healthcare, and critical infrastructure in Europe, where Linux servers and endpoints are prevalent. Additionally, embedded devices and IoT systems running Linux with WiFi capabilities could be affected, potentially impacting operational technology environments. The absence of known exploits reduces immediate risk, but the vulnerability's presence in the kernel WiFi stack means that attackers with network proximity could attempt exploitation. Disruption of wireless connectivity or kernel crashes could also affect availability, impacting business continuity. Overall, the vulnerability poses a moderate risk that requires timely patching to prevent potential exploitation in European organizations relying heavily on Linux-based wireless systems.

European organizations should prioritize updating their Linux kernel versions to the patched releases that address CVE-2024-35937. Since the vulnerability resides in the cfg80211 WiFi subsystem, kernel updates from trusted Linux distributions (e.g., Debian, Ubuntu, Red Hat, SUSE) should be applied promptly. Network administrators should audit wireless network configurations to limit exposure, such as segregating WiFi networks and restricting access to trusted users and devices. Employing network segmentation and monitoring for anomalous wireless traffic can help detect attempts to exploit malformed A-MSDU frames. For embedded and IoT devices, vendors should be contacted to obtain firmware updates or mitigations. Where immediate patching is not feasible, disabling WiFi interfaces or restricting wireless access can reduce attack surface. Additionally, organizations should ensure robust logging and intrusion detection systems are in place to identify suspicious kernel or network behavior. Regular vulnerability scanning and compliance checks should include verification of kernel versions and patch status related to this vulnerability. Finally, educating IT staff about the nature of this vulnerability and its potential impact will improve incident response readiness.