How can I easily repair varnished cabinets where water has splashed on them?

My bathroom and kitchen cabinet doors have been damaged slightly by having had water splashed or dripped down on them. The varnish or poly that is on the cabinets seems to have "washed away" in several places. Is there some way to easily patch them? I'm getting the house ready to sell, and do not want to completely strip, sand, stain and etc. Can you help me? The cabinets are oak with a golden stain.