No , the attacker found an exploitable bug, and the blockchain is being rewound to undo it, but now we all can ask, 'what else would warrant rewind of blockchain', and this is the problem.
Quote
On 6 August 2010, a major vulnerability in the bitcoin protocol was spotted. Transactions weren't properly verified before they were included in the transaction log or blockchain, which let users bypass bitcoin's economic restrictions and create an indefinite number of bitcoins. On 15 August, the vulnerability was exploited; over 184 billion bitcoins were generated in a transaction, and sent to two addresses on the network. Within hours, the transaction was spotted and erased from the transaction log after the bug was fixed and the network forked to an updated version of the bitcoin protocol. This was the only major security flaw found and exploited in bitcoin's history.
The highlighted portion is essentially what has happened. The difference is that bitcoin knew about it for over a week, while we didnt find out about it until the attack was under way. Also, I announced in realtime block 235300, which is the stopping of a chain.
If there is a bug in the future that allows to totally bypass the coin emission, then we will fix that to. You can count on that.
Who replaces the coins dumped on exchanges once the exchanges rollback the transactions?