Position-Adaptive Mutation Scheduling Strategy in Fuzzing
The seed-adaptive mutation scheduling strategy is the latest technology in mutation-based fuzzing,which can adaptively adjust the probability distribution of the mutation operators according to the syntax and semantic characteristics of the seed.However,it has two problems:(1)it is unable to adaptively adjust the probability distribution according to the mutation position;(2)The Thompson Sampling algorithm used in the fuzzing scenario is easy to lead to the learned probability distribution close to the average distribution,which leads to the failure of the mutation scheduling strategy.Focusing on the above problems,a position-adaptive mutation scheduling strategy is proposed.This technology establishes the relationship between the mutation position and the mutation operators through a user-defined double-layer multi-armed bandit model,and uses the Upper Confidence Bound algorithm to select the mutation operator,so as to achieve position adaptation and avoid the problem of average distribution.The position-adaptive fuzzer Position-Adaptive Mutation Scheduling Strategy AFL(PAMSSAFL)is implemented based on American Fuzzy Lop(AFL).The comparison results show that the position-adaptive mutation scheduling strategy can improve the bug detection ability and coverage ability of the fuzzer.