The article proposes an adaptive model for choosing strategies for financing cybersecurity means of an informatization object with incomplete information about the financial resources of the attacking party. The case is considered when the financial resources of the side of the defense belong to some fuzzy set. The model is intended for the developed decision support system in the tasks of choosing rational options for investing in information security systems. The solution was obtained based on the use of the tools of the theory of multistage games with several terminal surfaces. The model is distinguished by the assumption that the
protection side does not have complete information about both the financial strategies of the attacking side and the state of its financial resources aimed at overcoming the boundaries of information protection. It is assumed that the defense side has the ability to obtain additional information at the expense of part of its financial resources. The performance of the model was checked using a computational experiment, the results of which are also presented in the article.