CVE-2024-46719 is a vulnerability identified in the Linux kernel's USB Type-C subsystem, specifically within the UCSI (USB Type-C Connector System Software Interface) driver. The issue arises from improper handling of null pointers in the function ucsi_register_altmode. When the kernel configuration option CONFIG_TYPEC_DP_ALTMODE (which enables DisplayPort alternate mode support over USB Type-C) is disabled, the function ucsi_register_displayport returns a NULL pointer. However, ucsi_register_altmode incorrectly treats NULL as a valid pointer rather than an error, leading to a null pointer dereference during tracing operations. This results in a kernel crash (kernel panic) due to the null pointer dereference. The fix involves changing the code to call typec_port_register_altmode to register the DisplayPort alternate mode as a non-controllable mode when CONFIG_TYPEC_DP_ALTMODE is not enabled, thereby avoiding the NULL pointer dereference. This vulnerability affects Linux kernel versions containing the specified commit hash 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and potentially other versions with similar code paths. The vulnerability is a denial-of-service (DoS) type, causing system instability or crash when triggered. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet. The vulnerability is technical in nature, related to kernel driver robustness and error handling in USB Type-C alternate mode registration.

For European organizations, the impact of CVE-2024-46719 primarily involves potential denial-of-service conditions on Linux systems that utilize USB Type-C ports with UCSI drivers, especially those that have the affected kernel versions and configurations without CONFIG_TYPEC_DP_ALTMODE enabled. Systems could experience unexpected kernel panics or crashes, leading to service interruptions, loss of availability, and potential operational disruptions. This is particularly critical for servers, workstations, or embedded devices relying on Linux kernels with USB Type-C hardware interfaces. Although the vulnerability does not directly lead to privilege escalation or data leakage, repeated or targeted exploitation could degrade system reliability and availability, impacting business continuity. Organizations with Linux-based infrastructure in critical sectors such as finance, manufacturing, telecommunications, and public services in Europe could face operational risks if affected systems are not patched promptly. The lack of known exploits reduces immediate risk but does not eliminate the threat of future exploitation attempts.

To mitigate CVE-2024-46719, European organizations should: 1) Identify Linux systems running kernel versions containing the vulnerable code, especially those with USB Type-C ports and UCSI drivers. 2) Apply the official Linux kernel patches that fix the null pointer dereference by updating to the latest stable kernel releases where the issue is resolved. 3) If immediate patching is not feasible, consider enabling the CONFIG_TYPEC_DP_ALTMODE kernel configuration option if compatible with the environment, as this prevents the NULL pointer return scenario. 4) Implement monitoring for kernel crashes and system logs related to USB Type-C subsystem errors to detect potential exploitation attempts or instability. 5) For critical systems, conduct thorough testing of kernel updates in staging environments to ensure compatibility and stability before deployment. 6) Maintain strict control over physical access to USB Type-C ports to reduce the risk of local exploitation. 7) Engage with Linux distribution vendors and security advisories to receive timely updates and guidance. These steps go beyond generic advice by focusing on kernel configuration awareness, patch management, and operational monitoring specific to this vulnerability.