Line the base of your cabinet with this Sink Base Drip Tray from Rev-A-Shelf to help prevent damage from water leaks and spillage. The tray is designed with a slope that will push water out of the cabinet onto the floor, so you are aware of a leak and the bottom of the cabinet is protected from water damage.
The tray, which is resistant to most household chemicals, comes in a variety of sizes and can be trimmed to fit with a utility knife.
The tray is available on Amazon.com and Walmart.