The way in which the bitcoin market works makes it "imposible", that is, it is possible but in a certain way it is absurd. The blockchain system works because of all the transactions in the world are recorded on all the computers of the world and for to be able to hack a transaction or make money appear from where it was not, you will have to hack every computer that has records, which in theory is possible, but that, being reasonable, is almost impossible and if we add the fact that the value of the bitcoin is given by the trust that people place in it, and if an exaggerated masive hack happen people would lose all the confidence in the bitcoin or any othe cryptocurrency and it wouldn't has value, so, whatever be the point of view where you focus it, that will no happen.