CVE-2022-49845 is a vulnerability identified in the Linux kernel, specifically within the Controller Area Network (CAN) protocol stack implementation related to the J1939 protocol. The vulnerability arises from a missing initialization of the CAN header in the function j1939_send_one(), which is responsible for sending CAN frames. More precisely, the issue involves uninitialized reserved elements in the struct can_frame, which are later accessed via the struct canxl_frame::len field inside a socket buffer (skbuff) created by the J1939 protocol handler. The absence of proper zero-initialization of the 8-byte CAN header can lead to the use of uninitialized memory, potentially causing undefined behavior such as information leakage or memory corruption. The patch for this vulnerability ensures that the CAN header is fully zero-initialized before use, mitigating the risk of unintended data exposure or instability. Although the vulnerability does not have a CVSS score assigned yet and no known exploits are reported in the wild, the flaw resides in a critical kernel subsystem that handles automotive and industrial CAN communications, which are increasingly relevant in embedded Linux environments and IoT devices. Given the kernel-level nature of the flaw, exploitation could impact system stability or security depending on the context in which the CAN interface is used.

For European organizations, the impact of CVE-2022-49845 depends largely on their use of Linux-based systems that interact with CAN bus networks, particularly those implementing the J1939 protocol. This protocol is widely used in automotive, transportation, and industrial control systems. Organizations involved in automotive manufacturing, logistics, public transportation, and industrial automation may be at risk if their Linux systems handle CAN traffic without the patch. Potential impacts include system crashes, data leakage from uninitialized memory, or even privilege escalation if the vulnerability is chained with other flaws. Given the increasing adoption of Linux in embedded systems across Europe, especially in automotive hubs like Germany and France, unpatched systems could face operational disruptions or security breaches. However, since no active exploitation is known, the immediate risk is moderate but could escalate if attackers develop exploits targeting this kernel flaw.

To mitigate CVE-2022-49845, European organizations should prioritize updating their Linux kernel to the latest patched versions that include the fix for the CAN header initialization. Specifically, kernel maintainers and system administrators should apply the official patches or upgrade to kernel versions released after the vulnerability disclosure date (post-May 2025). For embedded and IoT devices that use custom or long-term support kernels, vendors should be contacted to provide updated firmware incorporating the fix. Additionally, organizations should audit their use of CAN interfaces and restrict access to these interfaces to trusted processes only, minimizing the attack surface. Implementing strict kernel module loading policies and using security modules like SELinux or AppArmor can help contain potential exploitation. Network segmentation and monitoring of CAN traffic for anomalies can also provide early detection of attempts to exploit this vulnerability. Finally, organizations should maintain an inventory of Linux systems with CAN capabilities to ensure timely patch management.