CVE-2025-37831 is a vulnerability identified in the Linux kernel's CPU frequency scaling subsystem, specifically within the apple-soc cpufreq driver. The issue arises in the function apple_soc_cpufreq_get_rate(), which calls cpufreq_cpu_get_raw() to retrieve the raw CPU frequency rate. However, cpufreq_cpu_get_raw() can return a NULL pointer if the target CPU is not present in the policy->cpus mask, a condition that apple_soc_cpufreq_get_rate() does not currently check for. This lack of validation leads to a NULL pointer dereference vulnerability. When the function attempts to dereference this NULL pointer, it can cause a kernel panic or system crash, resulting in a denial of service (DoS). The vulnerability affects Linux kernel versions identified by the provided commit hashes, which correspond to recent kernel versions incorporating the apple-soc cpufreq driver. This driver is primarily used on Apple Silicon-based SoCs running Linux, such as Apple M1 or M2 chips, which have increasing support in the Linux kernel. Although no known exploits are currently reported in the wild, the vulnerability's nature as a NULL pointer dereference in kernel space means that an attacker with the ability to trigger the affected code path could cause system instability or crashes. The vulnerability does not appear to allow privilege escalation or arbitrary code execution directly but can be leveraged to disrupt system availability. The issue was publicly disclosed on May 8, 2025, and a patch has been released to add the necessary NULL pointer checks to prevent dereferencing. This vulnerability is specific to the apple-soc cpufreq driver and thus affects Linux systems running on Apple Silicon hardware with this driver enabled.

For European organizations, the impact of CVE-2025-37831 primarily concerns systems running Linux on Apple Silicon hardware, which is less common in enterprise environments compared to x86_64 architectures but is growing in popularity, especially in development, research, and specialized computing contexts. The vulnerability can cause kernel crashes leading to denial of service, which may disrupt critical services, reduce system availability, and impact operational continuity. Organizations using Apple Silicon Linux systems for development, testing, or production workloads could face unexpected downtime or system instability. Although the vulnerability does not directly compromise confidentiality or integrity, the availability impact can be significant in environments requiring high uptime or real-time processing. Additionally, if exploited in multi-tenant or shared environments, such as cloud or virtualized setups using Apple Silicon hosts, it could affect multiple users or services. The lack of known exploits reduces immediate risk, but the vulnerability should be addressed proactively to avoid potential exploitation as attackers develop techniques to trigger the NULL pointer dereference. Overall, the threat is moderate but relevant for organizations adopting Apple Silicon Linux platforms in Europe.

To mitigate CVE-2025-37831, European organizations should: 1) Apply the official Linux kernel patches that fix the apple_soc_cpufreq_get_rate() NULL pointer dereference as soon as they become available and have been tested in their environments. 2) For systems running Apple Silicon hardware with Linux, ensure kernel versions are updated to include the fix, especially in production or critical systems. 3) Monitor kernel logs and system stability for signs of crashes or anomalies related to CPU frequency scaling. 4) Limit access to systems running vulnerable kernel versions to trusted users and networks to reduce the risk of triggering the vulnerability. 5) In virtualized or containerized environments, isolate Apple Silicon Linux hosts and apply strict resource and access controls to prevent unauthorized triggering of the vulnerable code path. 6) Engage with hardware and Linux distribution vendors to confirm patch availability and deployment timelines. 7) Incorporate this vulnerability into vulnerability management and patching workflows to ensure timely remediation. These steps go beyond generic advice by focusing on the specific hardware and kernel driver affected and emphasizing proactive monitoring and access control in relevant environments.