Rethinking about guessing attacks

Although various past efforts have been made to characterize and detect guessing attacks, there is no consensus on the definition of guessing attacks. Such a lack of generic definition makes it extremely difficult to evaluate the resilience of security protocols to guessing attacks. To overcome this hurdle, we seek a new definition in this paper to fully characterize the attacker's guessing capabilities (i.e., guessability). This provides a general framework to reason about guessing attacks in a symbolic setting, independent of specific intruder models. We show how the framework can be used to analyze both passive and active guessing attacks.