CVE-2025-38003 is a vulnerability identified in the Linux kernel specifically related to the Controller Area Network (CAN) subsystem's Broadcom (bcm) driver implementation. The issue arises from missing Read-Copy-Update (RCU) read-side protection when generating procfs content for bcm operations (bcm_op) that are in the process of being removed. The procfs filesystem in Linux exposes kernel data structures to user space, and in this case, when procfs content is generated for a bcm_op undergoing removal, the output may reflect unreliable or stale data due to a use-after-free (UAF) condition. This occurs because the bcm_op list entries are not properly protected by rcu_read_lock(), which is necessary to ensure safe concurrent access during removal. The vulnerability is addressed by adding the missing rcu_read_lock() calls and ensuring that list entries are correctly removed under RCU protection, preventing access to freed memory. Although the vulnerability does not have a CVSS score yet and no known exploits are reported in the wild, the underlying issue is a classic concurrency and memory safety flaw that could potentially lead to kernel crashes or information disclosure if exploited. The affected versions include multiple Linux kernel commits identified by their hashes, indicating that this vulnerability impacts specific kernel builds prior to the patch. The vulnerability was published on June 8, 2025, and is classified as a kernel-level vulnerability affecting the Linux operating system, which is widely used in servers, embedded systems, and network devices.

For European organizations, the impact of CVE-2025-38003 could be significant, especially for those relying on Linux-based infrastructure in critical environments such as telecommunications, industrial control systems, automotive systems, and data centers. The CAN subsystem is often used in embedded and automotive contexts, so organizations involved in automotive manufacturing, IoT device deployment, or industrial automation could be particularly affected. Exploitation of this vulnerability could lead to kernel instability, system crashes, or potential information leakage through corrupted procfs data, undermining system reliability and confidentiality. While no public exploits are known yet, the vulnerability's nature as a use-after-free in kernel space means that a successful exploit could allow local attackers or compromised processes to escalate privileges or cause denial of service. This could disrupt business operations, impact service availability, and potentially expose sensitive operational data. Given the widespread use of Linux in European IT infrastructure, the vulnerability poses a risk to sectors including finance, healthcare, manufacturing, and government services that depend on stable and secure Linux environments.

To mitigate CVE-2025-38003, European organizations should prioritize updating their Linux kernel to the patched versions that include the fix for the missing RCU read protection in the bcm CAN driver. Kernel updates should be tested in staging environments to ensure compatibility with existing applications and hardware. Organizations using custom or embedded Linux distributions should coordinate with vendors or maintainers to integrate the patch promptly. Additionally, system administrators should audit systems that utilize the CAN subsystem, particularly in automotive or industrial contexts, to identify vulnerable kernel versions. Employing kernel hardening techniques such as Kernel Address Space Layout Randomization (KASLR), Kernel Page Table Isolation (KPTI), and enabling security modules like SELinux or AppArmor can reduce the risk of exploitation. Monitoring kernel logs and procfs outputs for anomalies may help detect attempts to exploit the vulnerability. Finally, restricting local user access and minimizing unnecessary privileges can limit the attack surface, as exploitation likely requires local access to the system.