could use wired connections to the vehicle to manipulate the vehicle, such as controlling the display dashboard, killing the engine, disturbing the steering, etc. However, the demonstrations do not attract much attention from the audience. In recent years, the advancement in AV technology allows diverse types of sensors to be installed on the vehicle to assist human driving. For example, Google's driverless car utilizes more than 10 types of sensors to move autonomously on the road. However, sensors are easily affected by noise and fooled by malicious attacks, which can cause danger and accidents [4; 5]. Due to people's concerns regarding the AV reliance, many efforts have been dedicated to the studies of AV security and safety issues. As AVs have evolved, many types of wireless connectivity technologies have been installed on the vehicle, such as Bluetooth, keyless remote entry, telematics connected to the internet, and VANET, etc. The increased connectivity not only provides more convenience and better safety for the driver, but also speeds up the development of subsequent automation. However, the expansion of vehicle connectivity exposes more vulnerabilities of the vehicle and increases the opportunities for attackers to implement cyber-attacks. Paper [6] showed that a vehicle can be compromised through a Bluetooth connection meters away from the vehicle. In [3], the authors showed that the attackers successfully hacked an unaltered Jeep Cherokee through the cellular network and then controlled the vehicle's critical functions remotely, such as disabling the brakes and steering, etc. In [4], the authors investigated potential cybersecurity threats to both individual automated vehicles and cooperative automated vehicles. In [5], the authors surveyed cyber threats facing CAVs from three aspects of vehicles, human, and connection infrastructure. Recently, with the flourishing and advancement of IoT and sensing networks, the CAV and even Internet of Vehicles are deeply involved in intelligent transportation and smart city development. Thus, Paper [7] provided detailed analyses on characteristics, architecture, and challenges of intelligent transportation systems. Paper [8] comprehensively investigated how the smart city development imposes precedented security and privacy challenges on intelligent transportation and intelligent infrastructures, such as smart parking, intelligent navigation, and electrical vehicle charging, which illustrates the obstacles of widely deploying CAVs. Clearly, CAVs face great security risks. Although much effort has been dedicated to identifying security vulnerabilities and recommending potential mitigation techniques for AVs and CVs, respectively, there is still an absence of in-depth and comprehensive research to study how cyber-attacks can exploit the vulnerabilities of CAVs to negatively impact the physical operation and performance of CAVs. Therefore, the purposes of the work are to thoroughly investigate the potential vulnerabilities and security issues of CAVs from the viewpoints of individual autonomous vehicle technologies (e.g., sensors, in-vehicle systems) and connected vehicle technologies, and accordingly, to identify the negative impacts of cyber-attacks on the physical operation and performance of CAV from the perspectives of intra-vehicle systems and inter-vehicle systems. The work aims to create a future roadmap for CAV development and deployment. Figure 1 shows the cyber-attacks on CAV. The main contributions of the paper are as follows:  
1. A summary of the security issues and solutions for AVs associated with different sensors, controllers, and in-vehicle networks. 2. An investigation of the connectivity technologies of CVs and analysis of their advantages and applications in CAVs, as well as identifying the security issues of each type. 3. An analysis of the impact of cyber-attacks on CAVs: cyber-attacks on intra-vehicle systems to impact the individual CAVs and cyber-attacks on vehicle connectivity to impact the cooperative CAV. 4.