This is what noonsite says
http://www.noonsite.com/Countries/Cuba
Add CIA factbook
https://www.cia.gov/library/publicat...cu.html#Issues
Your paperwork would have to be well in order. Even at that you could lose your boat with no diplomatic resolution.
Can't really say it is a place of interest to me. Stay away from Git'mo if you don't want you boat ventilated with .50 cal rounds.
Unless you have some pressing need or divine guidance, there are other places to sail.