One of the key issues of information security is software vulnerabilities in computer systems. Malicious attackers can exploit security vulnerabilities to gain privileges, access unauthorized system resources, and even change sensitive data. The main purpose of this paper is the vulnerability model of distributed systems based on reliability theory. This paper directly analyzes the machine instruction, formulates the corresponding standard model, and studies the corresponding model control method. This paper presents an analytical method that uses reliability theory to introduce the Fuzzing random test method. The method uses static analysis techniques to gather information about the structure of the system, its interfaces, and useful code regions, and then develops test problems for executing the useful code regions-for which this paper uses genetic algorithms to understand. It guides the generation of test data and overcomes the shortcomings of random fuzzing methods in terms of large and unpredictable test data sets. The method also analyzes files that can be executed directly without the source code of the program. Experiments show that the vulnerability model system constructed in this paper is more realistic. The parallel login response time of the system in this paper is about 0.12s, and the parallel use response time is about 0.2s.