Novel method of assessing network security risks based on vulnerability correlation graph

In order to improve networks' total security, a method of assessing network security risks based on vulnerability correlation graph is proposed in this paper. Firstly, it proposed a definition of vulnerability correlation graph based on the basis of network security dependency. Secondly, according to the size of network topology, the method of assessing the potential risk based on the vulnerability correlation graph is explained in detail. The experiment results show that it's possible to calculate potential risk indexes of three hierarchies: hosts, subnets and networks so that system administrators could adjust the security strategies in order to reduce the potential risk value of the whole network. It is also possible to solve the problem of network state explosion, thus improving expansibility of the assessment method.