A vehicular ad hoc network (VANET) is a type of network that is used to create mobile nodes. It treats vehicles as mobile nodes and provides the means to communicate between vehicles for driving safely. Addressing the security requirements of inter-vehicle and vehicle-roadside communication plays an important role. In VANET, the vehicle nodes consist of On Board Unit (OBU) and Road Side Units (RSU). The RSU's are installed along the road. Vehicles communicate with each other and as well as with RSUs through wireless communications. VANET adopt Certificate Revocation Lists (CRLs) for their security. The sender certificate is included in the current CRL to verify the authenticity and signature of the sender. A trusted authority (TA) performs registration to vehicle users during which vehicles pseudonyms and secrets are updates and stored in the vehicles OBU. Secure communication and anonymous protocol is important in VANET. We propose an efficient CRL based secure communication protocol which focuses on detecting malicious node in vehicular communications.