Computer-based systems where several nodes exchange information via suitable network interconnections are today exploited in many safety-critical applications, like those belonging to the automotive field. Accurate dependability analysis of such a kind of systems is thus a major concern for designers. In this paper, we present an environment we developed in order to assess the effects of faults in CAN-based networks. We developed an IP core implementing the CAN protocol controller, and we exploited it to set-up a network composed of several nodes. Thanks to the approach we adopted, we were able to assess via simulation-based fault injection the effects of faults both in the bus used to carry information and inside each CAN controller as well. In this paper, we report a detailed description of the environment we set-up and we present some preliminary results we gathered to assess the soundness of the proposed approach.