Vehicular Ad-Hoc Network (VANET) applications are context-aware since they need environment and local contexts to operate properly and help their users on many aspects, like indicating the best route to take or warning about accidents and traffic congestion situations. These applications need a context provider system responsible for collecting, analyzing, reasoning and making contexts available to them. In this work we propose a smart context provisioning middleware, called ConProVA, that provides context information to applications, is able to infer logical context and deals with conflicts of interest. We evaluate through simulation an instance of ConProVA considering an accident detection and avoidance application. The results show that it is possible to improve the users' satisfaction by reducing total travel time and carbon dioxide emission when accidents occur.