This is not a new revelation and all the exchanges are under attack constantly and it is always a battler between the hackers and the exchanges, be it bitcoin or stock exchanges and so is the reason you need high level of security to maintain everything without any issue and when a company fails to carry on their duties hackers will loot the money. All of the hacks happened in exchanges could have being avoided if those exchanges took security seriously.  

For all the users asking for a source, face palm  . The OP just created a random topic and everyone wants proof of those claims .