CVE-2024-26894 is a vulnerability identified in the Linux kernel's ACPI (Advanced Configuration and Power Interface) subsystem, specifically within the processor_idle driver component. The issue arises from a memory leak in the function acpi_processor_power_exit(), which is responsible for cleaning up resources when a CPU idle device is unregistered. The vulnerability occurs because the memory allocated for the CPU idle device is not properly freed after the device is unregistered, leading to an unreferenced object remaining in memory. This leak can cause gradual exhaustion of kernel memory resources, potentially degrading system performance or causing instability over time. The backtrace provided indicates the leak occurs during the driver unregister process, involving kernel functions such as kmalloc_trace and acpi_processor_power_init. The flaw is categorized under CWE-770 (Allocation of Resources Without Limits or Throttling), indicating improper resource management. The vulnerability has a CVSS 3.1 base score of 6.0, reflecting a medium severity level. The vector details indicate that exploitation requires local access (AV:L), low attack complexity (AC:L), privileges (PR:H), no user interaction (UI:N), unchanged scope (S:U), with high confidentiality impact (C:H), no integrity impact (I:N), and high availability impact (A:H). No known exploits are reported in the wild as of the publication date (April 17, 2024). The fix involves modifying the kernel code to ensure that the CPU idle device memory is freed after unregistration, preventing the leak. This vulnerability affects Linux kernel versions identified by the provided commit hashes, which correspond to recent kernel releases prior to the patch. Given the Linux kernel's widespread use in servers, desktops, and embedded systems, this vulnerability is relevant to a broad range of environments.

For European organizations, the impact of CVE-2024-26894 can be significant, especially for those relying heavily on Linux-based infrastructure such as servers, cloud platforms, and embedded devices. The memory leak can lead to gradual degradation of system stability and availability, potentially causing service interruptions or crashes in critical systems if the leak accumulates over time without a reboot or remediation. This is particularly concerning for data centers, telecommunications providers, and industries with high uptime requirements such as finance, healthcare, and manufacturing. The high confidentiality impact in the CVSS vector suggests that the leak might expose sensitive kernel memory contents under certain conditions, although the primary concern is availability. Since exploitation requires local privileged access, the threat is more relevant in environments where attackers or malicious insiders already have elevated privileges or where privilege escalation vulnerabilities exist. European organizations with strict data protection regulations (e.g., GDPR) must consider the risk of confidentiality breaches and service disruptions. Additionally, embedded Linux devices used in critical infrastructure or IoT deployments across Europe could be affected, potentially impacting operational technology systems.

1. Immediate application of the official Linux kernel patches that address CVE-2024-26894 is the most effective mitigation. Organizations should track kernel updates from their Linux distribution vendors and apply security updates promptly. 2. For environments where immediate patching is not feasible, implement monitoring of kernel memory usage and system stability to detect signs of memory leaks early. 3. Limit local privileged access to trusted personnel only and enforce strict access controls and auditing to reduce the risk of exploitation by insiders or attackers with local access. 4. Employ kernel hardening techniques such as SELinux or AppArmor to restrict the capabilities of processes and reduce the attack surface. 5. For embedded or IoT devices running affected Linux kernels, coordinate with device vendors for firmware updates or consider device replacement if patches are unavailable. 6. Regularly reboot systems as a temporary measure to clear leaked memory, though this is not a long-term solution. 7. Conduct vulnerability scanning and penetration testing focused on privilege escalation paths that could enable an attacker to gain the required local privileges to exploit this vulnerability.