Replaced the water filter casing (the part that the water filter screws into). There is a tiny plastic piece that the filter pushes in that allows the water to come out at the bottom of the casing that was slowly leaking water. Figuring out how to get the old casing off was the tricky part. There is a tiny red piece at the base of the white tube that has to be pulled out, then you have to push the tube into the casing and use a pliers to keep the gray sleeve from pulling out while you pull the white tube out.
Samsung RSG307AARS/XAA