We have studied a model of a hard sphere fluid adsorbed in a cylindrical and spherical pore filled with a quenched disordered matrix of hard sphere particles using Grand canonical Monte Carlo simulations. The interactions of both matrix and fluid species with pore walls are assumed to be of a hard sphere type. We discuss the adsorption isotherms and density profiles of fluid particles in pores with different microporosities for several values of pore radius. We have observed that, similar to homogeneous microporous media, the adsorption increases with increasing porosity. However, trends of behavior of the isotherms also reflect layering of adsorbed fluid. The data obtained serve as a benchmark for the development of the theory of confined quenched-annealed systems and for computer simulation investigation of models permitting phase transitions in pores.