Cognitive radio, ad hoc networks' applications are continuously increasing in wireless communication globally. In vehicles' environment, cognitive radio technology with mobile ad hoc networks (MANETs) enables vehicles to monitor the available channels and to effectively function in these frequencies through sharing ongoing information with drivers and different frameworks to enhance traffic safety on roads. To fulfill the computational storage resources' limitations of a specific vehicle, Vehicular Cloud Computing (VCC) is used by merging VANET with cloud computing. Cloud computing requires high security and protection because authenticate users and attackers have the same rights in VCC. The security is enhanced in CRVANETs, but the distributed nature of cloud unlocks a door for dissimilar attacks, such as trust modal, data security, connection fault and query tracking attacks. This paper proposes an effective and secured blockchain scheme-based distributed cloud architecture in place of conventional cloud architecture to secure the drivers' privacy with low cost and on-demand sensing procedure in CRVANETs ecosystem.