The multivariable theory of nucleation in Langevin's approach [N.V. Alekseechkin, J. Chem. Phys. 124, 124512 (2006); N.V. Alekseechkin, J. Chem. Phys. 129, 024512 (2008)] is applied to the problem of vapor bubbles formation in a liquid with arbitrary viscosity. The obtained expression for the nucleation rate of bubbles is valid for arbitrary relations between the kinetic parameters controlling the nucleation process: viscosity, inertia of a liquid, the rate of evaporation into a bubble and the rate of heat exchange between the bubble and ambient liquid. So, the presented theory yields a complete description of the vapor-bubbles nucleation kinetics in single-component liquids. Limiting cases with respect to the mentioned parameters are considered, in particular, the low-viscosity limit. It is shown that the low-and high-viscosity nucleation rates differ from each other qualitatively and quantitatively. The possibility of application of the theory to cavitation in superfluid helium-4 is discussed.