Sea water is very salty…if it is only slightly salty its probably fresh water. Fresh water invariably comes from rain leaking in somewhere. I traced the source of my fresh water leak to the screws on the tow rail on port side just forward of the shrouds. I loosened about 10 (c. 10mm) and injected clear silicone sealant onto threads before re – tightening. Other possibilities are the shroud plates at deck level or head sail sheet track. The other area I got rain water (only into engine compartment) was via vents in companion way. I now cover these when I leave the boat while I look for a more permanent solution.
If its sea water then it might be ill fitting toe rail letting in water on beat…unlikely to be keel.
Have you tried drying it out completely and then looking for ingress while playing a hose in specific suspect areas?