If you do not go into the city, then a transit visa is not required.

In this case, you will not need a Schengen visa. The flight by Air France-Moscow-Paris-Havana provides for docking at the French airport Charles de Gaulle. If docking lasts no more than 24 hours, then a transit visa is not needed. However, with this option, you will not be allowed to leave the transit zone of the airport.

If a passenger from Moscow arrives at Charles de Gaulle airport and from there he needs to transfer to Orly airport for a flight to, say, Casablanca, transit a visa is required. And it does not matter how much time it will take in Paris - more than a day or a couple of hours.