Security management of information systems is a very important part of the company management in entirety. The amount of data to be processed and stored every day is increasing and often at the same time becomes an advantage and a disadvantage. Data are used either only for forensic analysis or not used at all. The aim of this paper is to use data stored in information systems to propose a model for calculating the probability of future events. The event regarding the thesis of the paper is often determined by the parameters of the environment whose intensity can affect the outcome of the event and its impact on information systems. The Bayes' Theorem is used by which it is possible to calculate the probability of realization of events based on probability of monitored parameters. The paper presents the results of experiments in which they studied modes of models within different environments. The goal is to find the optimal way of working and define conditions that must be met to achieve the desired results. Results are presented through proper draft decisions on the basis of which it is possible to take corrective and preventive actions. Evaluation of results is also performed in different ways. The results of simulations whose results can be compared with the corresponding system or tools are evaluated by comparison with reference results. Evaluations are conducted also through comparison with the opinion of experts in the field of management information systems. All results are equally evaluated using accuracy indicators. The model presented in this paper can be used in the described environments, as well as a separate module in larger systems where it is necessary to monitor certain systems through monitoring the parameters of the environment. Agent mode is advantageous because it allows managing systems in real time. The biggest advantage of the model is the possibility of application in different environments but not necessarily within the management of information systems but also business and social characteristics of systems that are driven by information and communication technology.