More attention is given to safety of end users from the use of applications in vehicular networks; therefore it is vitally important that these applications are veiy secure in order to ensure dependable service for users and adequate safety of human life. Though unwanted, the attacker is also one of the major entities that can critically affect new potentially lifesaving vehicular network. These bothersome attackers behave in very unpredictable ways and can launch various kinds of attacks. In this paper, practically all possible attacks in a vehicular network are divided into five different classes. We also discussed some possible new kinds of attacks on lifesaving networks. The main reason for assigning classes to these attacks is to enable identification and classification of the various attacks that are perpetrated in a vehicular environment for use in designing new solutions. © 2013 International Information Institute.