CVE-2024-56590 is a vulnerability identified in the Linux kernel's Bluetooth subsystem, specifically within the hci_core component responsible for handling Bluetooth Host Controller Interface (HCI) data packets. The vulnerability arises from improper validation of the length of socket buffer (skb) data when processing ACL (Asynchronous Connection-Less) data packets. The affected code fails to verify that the skb actually contains a valid ACL header before attempting to access it. This can lead to the kernel accessing uninitialized or invalid memory beyond the valid skb->data buffer. Such out-of-bounds memory access can cause undefined behavior including potential kernel crashes (denial of service) or memory corruption, which could be leveraged by an attacker to escalate privileges or execute arbitrary code within the kernel context. The flaw is rooted in insufficient input validation in the Bluetooth HCI data packet processing path. The vulnerability affects multiple versions of the Linux kernel as indicated by the repeated affected version hashes, suggesting a widespread impact across various kernel builds. Although no known exploits are currently reported in the wild, the nature of the vulnerability in a critical kernel subsystem and the potential for memory corruption make it a significant security concern. The issue was publicly disclosed on December 27, 2024, and a patch has been released to address the problem by adding proper length checks before accessing the ACL header in skb data buffers.

For European organizations, the impact of CVE-2024-56590 can be substantial, particularly for those relying on Linux-based systems with Bluetooth capabilities. The vulnerability could be exploited by an attacker with local or possibly remote Bluetooth access to cause kernel crashes, leading to denial of service conditions on critical infrastructure, servers, or endpoint devices. In more severe scenarios, exploitation might allow privilege escalation or arbitrary code execution at the kernel level, compromising system integrity and confidentiality. This poses risks to sensitive data, operational continuity, and compliance with data protection regulations such as GDPR. Organizations in sectors like manufacturing, healthcare, telecommunications, and government, which often use Linux systems with Bluetooth for device management or IoT integration, may face increased exposure. The vulnerability's exploitation could disrupt business operations, lead to data breaches, or facilitate lateral movement within networks. Given the kernel-level nature of the flaw, remediation complexity and potential downtime during patching must also be considered.

European organizations should prioritize the following mitigation steps: 1) Immediate deployment of the official Linux kernel patch that addresses CVE-2024-56590 to ensure the Bluetooth HCI core properly validates skb lengths before processing ACL data packets. 2) Conduct thorough inventory and identification of all Linux systems with Bluetooth enabled, including embedded devices and IoT endpoints, to ensure comprehensive patch coverage. 3) Where patching is not immediately feasible, consider disabling Bluetooth functionality temporarily on critical systems to reduce attack surface. 4) Implement network segmentation and strict access controls to limit Bluetooth device connectivity to trusted devices only. 5) Monitor system logs and kernel messages for unusual Bluetooth activity or crashes that may indicate attempted exploitation. 6) Incorporate this vulnerability into vulnerability management and incident response plans to ensure rapid detection and remediation. 7) Engage with Linux distribution vendors and security advisories for updates and best practices related to this vulnerability. These targeted actions go beyond generic advice by focusing on Bluetooth-specific controls and kernel patch management tailored to this vulnerability.