Remove the 2 plastic caps from the mounting bracket access holes.
Drive a wood screw (Φ 4.5 x 12 mm) through the mounting bracket and into the cabinet frame.
Reinstall the plastic caps.
External water leakage could result if the installation of the screws to the surrounding timber cabinet is not done correctly.
Please ensure that the height levelling of the dishwasher is done by adjusting the feet before installing the side cabinet securing screws.