A recently patched security flaw in Tesla’s telematics control unit (TCU) allowed attackers with physical access to gain root-level code execution, raising concerns about connected vehicle security. The vulnerability was found in the TCU’s Micro USB port on firmware version v12 (2025.2.6), which runs the ADB daemon with root privileges. NCC Group researchers found that while Tesla had disabled direct shell access, two key ADB features, file transfer and port forwarding, remained active. This oversight created a straightforward pathway for attackers to bypass existing security measures and execute arbitrary code.
The exploit took advantage of the system’s trust in these ADB functions. An attacker would connect to the TCU via the Micro USB port. Then, they would use adb push to upload a malicious script to a writable directory on the TCU. Next, by writing the script’s path to the kernel’s uevent_helper file, they could trick the system into executing the script with root privileges. The script would then be triggered by a simple system event, such as a file transfer command. Finally, with the script running, the attacker could establish a remote shell connection, giving them full, unrestricted access to the TCU. The ability to gain root access on a critical component like the TCU is a major security risk, as it could allow for the modification of core vehicle functions, data theft, or lateral movement into other in-vehicle networks.
This incident highlights that physical attack surfaces are a significant and often overlooked risk in modern vehicles. While this flaw required physical proximity, its exploitation pathway demonstrates how even partially-secured administrative tools like ADB can leave critical security gaps. The vulnerability’s severity lies in the elevated privileges it provides; root access could potentially be a pivot point into other internal vehicle networks, raising concerns about safety and operational integrity. Although no evidence of active exploitation has been found, the disclosure serves as a critical reminder that vulnerabilities can be exploited during vehicle service, repair, or by tampering. As vehicles increasingly resemble mobile computing platforms, the security risks they face are converging with those of traditional IT, OT, and IoT systems.
While Tesla has since patched the flaw with an over-the-air (OTA) software update, the incident reinforces the importance of adopting a layered security strategy for automotive systems. Vehicle manufacturers and security teams must treat vendor firmware patches as a high priority to close known vulnerabilities promptly. They should also implement robust monitoring for unusual system behavior and limit physical access to exposed ports. Regularly auditing diagnostic and debug interfaces is also crucial to ensure only essential ones remain enabled. The implementation of tamper detection mechanisms can also provide an additional layer of defense. A least privilege model and network segmentation can further minimize the impact of a potential breach.
This case serves as a crucial lesson that the security of modern vehicles is an integral part of a broader cybersecurity strategy. The fact that a partial lockdown of administrative tools could lead to such a significant vulnerability highlights the need for comprehensive threat modeling and a holistic security approach. As vehicles become more connected and software-defined, securing them against both remote and physical attacks will become an even greater challenge. For security professionals, this means treating automotive cybersecurity as part of the wider enterprise attack surface, applying best practices to a rapidly evolving technological landscape.
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