We always knew DES encryption had a backdoor and was intended to be cracked. The U. of Waterloo proved that many decades ago.
Having the secure file of hashed passwords has always been known as being reversible.
There is never going to be a way of preventing that.
That is because you do not have to get the right password.
All you need is to end up with the same hashed result.
And that is never computationally hard, just slow.