Vehicular Ad hoc NETwork (VANET) is an emerging paradigm in networking. It is a new form of Mobile Ad hoc NETwork (MANET). Its life saving characteristic has attracted the industry and researchers. In VANET vehicles are the nodes with mobility so does not have fixed infrastructure It serves safe and non safe applications in a wireless medium which makes it vulnerable to several attacks. Security is the most important concern in VANET due to open access medium. In this paper the authors present the comprehensive study of possible attacks and their possible solutions.