Let's say that "foo" and "bar" are two distinct passwords that have the same MD5 hash.
As a practical matter, we can basically say that never happens. Certainly not for passwords that are user selected and not designed to collide. And since the hash itself is hidden by bcrypt, the attacker won't know md5("foo") even if they were inclined to find a "bar" with the same hash.
As a practical matter, we can basically say that never happens. Certainly not for passwords that are user selected and not designed to collide. And since the hash itself is hidden by bcrypt, the attacker won't know md5("foo") even if they were inclined to find a "bar" with the same hash.