CVE-2024-46768 is a vulnerability identified in the Linux kernel, specifically within the hardware monitoring (hwmon) subsystem related to the hp-wmi-sensors driver. The issue arises because the BIOS may return no event data in response to a Windows Management Instrumentation (WMI) event. In such cases, the ACPI (Advanced Configuration and Power Interface) object passed to the WMI notify handler can be NULL. The vulnerability exists because the Linux kernel did not previously check for this NULL condition, potentially leading to improper handling of WMI events. The fix involves adding a check to detect when the ACPI object is NULL and ignoring the event to prevent any adverse effects. This vulnerability is primarily a robustness issue in the kernel's event handling mechanism for hp-wmi sensors, which are used to monitor hardware sensors on HP devices. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The vulnerability affects specific versions of the Linux kernel identified by the commit hash 23902f98f8d4811ab84dde6419569a5b374f8122. The issue was reserved and published in September 2024, and it has been enriched by CISA, indicating recognition by cybersecurity authorities.

The impact of CVE-2024-46768 on European organizations depends largely on their use of Linux systems running the affected kernel versions, particularly on HP hardware that utilizes the hp-wmi-sensors driver. If exploited, the vulnerability could cause kernel instability or crashes due to unhandled NULL pointers in the WMI event processing path, potentially leading to denial of service (DoS) conditions. While there is no indication of privilege escalation or data confidentiality breaches, system availability could be affected, especially in environments relying on continuous hardware monitoring and uptime. For critical infrastructure, industrial control systems, or data centers in Europe that use Linux on HP hardware, this could translate into operational disruptions. However, the lack of known exploits and the nature of the vulnerability suggest the risk is moderate. Organizations with automated patch management and updated Linux kernels will be less impacted. The vulnerability does not appear to allow remote code execution or unauthorized access, limiting its severity primarily to stability and availability concerns.

European organizations should prioritize updating their Linux kernels to versions that include the patch addressing CVE-2024-46768. Since the vulnerability is related to the hp-wmi-sensors driver, organizations using HP hardware should verify the presence of this driver and ensure it is updated. Specific mitigation steps include: 1) Applying the latest Linux kernel updates from trusted sources or distributions that have incorporated the fix. 2) For environments where immediate patching is not feasible, consider disabling the hp-wmi-sensors driver if hardware monitoring via this interface is not critical, to prevent the vulnerable code path from being triggered. 3) Implement monitoring for kernel crashes or unusual system logs related to WMI events to detect potential exploitation attempts. 4) Maintain robust backup and recovery procedures to minimize downtime in case of system instability. 5) Engage with hardware vendors and Linux distribution maintainers to confirm the deployment of patches and receive guidance on best practices. These steps go beyond generic advice by focusing on the specific driver and hardware involved and emphasizing proactive monitoring and fallback strategies.