The ornamental design for a surfaceconfiguration of a rear bumper for a vehicle, as shown and described.
FIG. 1 is a left perspective view of a surface configuration of a rear bumper for a vehicle according to our novel design, the right perspective view being mirror symmetrical;
FIG. 2 is a front view of the surface configuration of a rear bumper for a vehicle according to our novel design;
FIG. 3 is a right perspective view of the surface configuration of a rear bumper for a vehicle according to our novel design, the left perspective view being mirror symmetrical; and,
FIG. 4 is a left side view of the surface configuration of a rear bumper for a vehicle according to our novel design, the right side view being mirror symmetrical.