The spread of active attacks has become a frequent cause of vast systems breakdown in modern communication networks. In this paper, we first present a probabilistic modeling framework for the propagation of an energy-constrained mobile threat in a wireless ad hoc network. The introduced formulation is used to identify and evaluate different attack strategies and approaches, which in turn can help in the development of efficient countermeasures for such attacks. Through modeling and simulation, we evaluate the impact of various parameters associated with the operational characteristics of the mobile attack node - such as transmission radius, mobility, energy - on an outbreak spreading and the evolution of the network. Furthermore, we introduce a new metric which indicates the overall infection-capability of each attack strategy and characterize their ability to harm the network according to this metric