Even though vehicular ad-hoc networks (VANETs) bring tremendous benefits to society, yet they raise many challenges where the security and privacy concerns are the most critical ones. In this paper, we provide a detailed overview of the state-of-the-art security and privacy requirements in VANET. Also, a brief of the approaches that are proposed in the literature to fulfill these requirements is given in this paper. Besides that, a classification of the various VANET attacks based on the communication system layers is provided in this paper. In addition, the different types of VANET adversaries and attackers are presented here. In general, this paper aims to provide a good piece of information about VANET security and privacy, in order to be used as a tool to help researchers in this field in developing secure privacy-preserving approaches for VANET.