A cable bushing assembly and a method of sealing a cable penetration through a housing are provided. The bushing assembly includes an interior shell, a central cavity and at least one aperture between a first face and a second face. At least one cable passes through the bushing assembly. The bushing assembly also includes an exterior shell at least partially circumscribing the interior shell. A clasp is located between the interior shell and the exterior shell to prevent separation of the exterior shell from the interior shell. Packing material seals the at least one cable within the interior shell. A method of sealing a cable penetration includes providing a housing with an opening, inserting a bushing assembly into the opening, and securing the cable bushing.