Not really a bug, per se. But you don't ever have to secure a hyperdrive or even enter a carrier or battleship for one, to access the final mission. Which is kinda weird, considering a 'hyperdirve disroptor' is used to initiate the final mission.
Not only that, the 'hyperdrive' research is useless. While all other researches gives some benefit, be it in new tech or boosts or in advancement of the tech line.