Yes, the Axial UTB18 Capra 4WS RTR is designed to be waterproof. The electronics, including the Spektrum Firma 25A ESC, the SR515 5-channel receiver and the S664 25T servos, are protected against water and dust. This enables use in various weather conditions and on wet terrain.
Please note, however, that "waterproof" does not mean that the vehicle can be completely submerged. It is advisable to clean and dry the buggy after use in a damp environment to ensure the longevity of the components.