In recent years, the development of vehicular ad-hoc networks (VANETs) has received much attention in intelligent transportation systems (ITS). Unlike traditional ad-hoc networks, VANETs are emerging with unique characteristics that share similar technology with autonomous vehicles (AVs) and automated driving systems (ASDs). Communication between vehicles and the surrounding infrastructure unit, such as a roadside unit (RSU), must be secured, concise, and authentic. Hence, an access control system for the ad-hoc environment is required. We introduced a level-based controlled signcryption (LBS) scheme, which can be easily constructed and implemented into an access control system for VANETs environment. Our encrypted message has a short and constant size, which is better when compared with other attribute-based signcryption or encryption. Confidentiality, privacy, and authenticity are also provided in our scheme to ensure secure and authentic communication. Therefore, our scheme has addressed communication cost, scalability, security, and privacy issues in VANETs. This primitive can be applied to simplify attribute-based access control, as the only attribute required is an integer representing the security level. Our objective is to improve the quality and security of VANET communication. Moreover, an optional privacy mechanism in our scheme provides flexibility in controlling node privacy in VANETs.