Currently, serious investigations are made now in road security as a critical research domain. However, the majority of them are based on expensive infrastructure. In this paper, we propose a new scheme for warnings spreading between vehicles without any dependence on road foundation. A new concept of Active vehicle that combines the power of the intelligence ambient and the V2V technologies is introduced. For alert endorsement, we suggest a new model for trust management for VANET based on only the cooperation between "Active vehicles" in order to enhance their security states and to cut with the spread of false warnings through a vehicular network. (C) 2015 The Authors. Published by Elsevier B.V.