Yg0r

I had this bug too, it's because of vehicles hit boxes being way too large in the new build, I hope they'll fix this soon.
 
What I did is create a new game, exit the game, copy my map_p.bin file character, paste it in the new game, then go play on the new game and you'll be outside the vehicle since it's on a new map, you move your character away, save & exit the game, get your map_p.bin file back to your first game and that's it

What you could try is to download a cheat mod, for example the CheatMenu or Nercoforge and teleport yourself out of the vehicle.