In order to fulfill the organization goals and objectives, multilayered network architecture and various heterogeneous server environments are used. As the network architectures are complex, there is an increased demand in information security. So each organization needs to provide sufficient network security for the known and the unknown attacks according to its goals, requirements and objectives. Highly skilled hacker's everyday discovers the new threats in order to break the security bridge in each organization. Hence the organizations are forced to revise their security policies in order to handle the network vulnerabilities that are increasing day by day. So to handle this issue a proactive network strategy is proposed against network vulnerabilities such as fraud, information leakage, denial of service attack and so on. By this approach the network is scanned periodically and the threats are prioritized and evaluated accordingly.