LAUSR

The hierarchical network is the more effective platform, which provides multiple channels for various worm propagation. Thus, emerging worms can infect vulnerable hosts by scanning strategy and social media. However, the spread of scan-based worm is restrained due to uneven distribution of vulnerable hosts and NAT (Network Address Translation) technique. Meanwhile, topological dependency dictates to topology-based worm only infecting those hosts in social networks. To avoid their respective disadvantages, modern hybrid worm, which combines the above two propagation mechanisms, can implement efficient IP-address scanning by enhanced combination-scanning strategy, and spread more aggressively in social networks using enhanced reinfection mechanism. This paper presents a Hierarchical-Stochastic Propagation model to understand hybrid worm propagation. Inspired by hybrid worm, we design a new vaccine based on the Hierarchical-Measure Immunization strategy. For physical networking layer, we can estimate vulnerable-host distribution to find vulnerable hosts effectively through Maximum Likelihood estimation. For social networking layer, we use a novel propagation centrality measure to discover vital social nodes accurately. The experimental results show that our model can characterize the propagation mechanism of hybrid worms more comprehensively, and greatly outperforms state of the art models in terms of estimation accuracy. Meanwhile, our strategy is more effective to restrain the hybrid worm from spreading in networks.