CVE-2018-9314 in BMW
Summary
by MITRE
The Head Unit HU_NBT (aka Infotainment) component on BMW i Series, BMW X Series, BMW 3 Series, BMW 5 Series, and BMW 7 Series vehicles produced in 2012 through 2018 allows an attack by an attacker who has direct physical access.
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Analysis
by VulDB Data Team • 02/10/2020
The vulnerability identified as CVE-2018-9314 affects the Head Unit HU_NBT component within BMW vehicles spanning multiple model lines including the i Series, X Series, 3 Series, 5 Series, and 7 Series manufactured between 2012 and 2018. This represents a critical security flaw that resides in the infotainment system architecture, specifically targeting the vehicle's head unit which serves as a central hub for entertainment and connectivity functions. The vulnerability is particularly concerning because it can be exploited by an attacker who possesses direct physical access to the vehicle, eliminating the need for sophisticated remote attack vectors that would typically require network connectivity or wireless communication capabilities.
The technical flaw manifests in the insufficient security controls implemented within the HU_NBT component's firmware and hardware architecture, allowing unauthorized access to critical vehicle systems through physical interaction with the infotainment unit. This vulnerability falls under the category of physical attack surface exploitation where an attacker can directly interface with the vehicle's electronic control units through the head unit's accessible ports or interfaces. The attack vector leverages the lack of proper authentication mechanisms and access controls that should normally prevent unauthorized modification or extraction of data from vehicle systems. According to CWE classification, this vulnerability aligns with CWE-284 Access Control Issues, specifically involving inadequate protection of system resources through insufficient authentication or authorization controls. The flaw creates a pathway for attackers to potentially gain access to vehicle diagnostic interfaces, communication protocols, or other sensitive system components that should remain protected from unauthorized physical access.
The operational impact of this vulnerability extends beyond simple privacy concerns to encompass potential safety and security risks for vehicle occupants and the broader connected vehicle ecosystem. An attacker with physical access could potentially modify vehicle settings, access personal data stored within the infotainment system, or even manipulate vehicle functions that rely on the head unit's communication with other vehicle systems. This vulnerability creates a significant risk for vehicle owners as it removes the security boundary that should exist between legitimate vehicle users and unauthorized parties who gain physical access to the vehicle. The attack surface is particularly dangerous because it operates outside traditional cybersecurity defenses that typically protect against network-based threats, instead exposing the vehicle to risks that can be exploited through simple physical interaction with the infotainment hardware.
Mitigation strategies for this vulnerability must address both immediate physical security measures and longer-term software updates to strengthen access controls within the infotainment system. Vehicle owners should be advised to maintain physical security of their vehicles and avoid leaving them unattended in vulnerable locations where unauthorized access could occur. BMW should implement firmware updates that enforce stronger authentication mechanisms and access controls within the HU_NBT component, ensuring that any physical interaction with the system requires proper authorization. The remediation approach should incorporate principles from the ATT&CK framework, specifically addressing the T1059 Command and Scripting Interpreter and T1068 Exploitation for Privilege Escalation tactics that attackers might employ through this physical access vulnerability. Additionally, the fix should include enhanced logging and monitoring capabilities to detect unauthorized physical access attempts to the infotainment system, providing vehicle owners and security personnel with early warning capabilities when suspicious activities occur. The vulnerability demonstrates the critical importance of considering physical attack surfaces in automotive cybersecurity, as traditional network-based security measures prove insufficient against threats that exploit direct hardware access.