A rigid body moves on a circular Keplerian orbit in a central Newtonian gravitational field. The attitude libration of a body in vicinity of the stable equilibrium position, influenced by the principal moment of gravitational forces is considered. It is supposed that the body is affected by nonlinear quadratic perturbation moment of general form. The influence of perturbation moment on nonlinear oscillations of a body under the conditions of multifrequency resonance is studied.