Attackers chosen coins that are traded on big exchanges (in this case our friends from Bittrex) and made a double spend attack due to owning more than 51% hashes needed.

While technology behind the attack is not easy to explain it does what it says - makes a double spend of same money.

Imagine buying something, then getting money back right away.

This way hackers (or more like attackers) with big hashing power choose coins that will be easy enough for them to get money on.

Currently only CANN (CannabisCoin) market is still disabled which means Bittrex team acted fast and fixed attack problems with developers.

This is why its a good idea to not make PoW coins unless you are sure of big hashing power but rather make tokens on other solid networks like Bitshares Ethereum or Bitcoin.

If you know any of low hashrate power PoW coins, keep eye on them - they may be next to be attacked ie on other exchanges.

Follow, Resteem and VOTE UP @kingscrown creator of http://fuk.io blog for 0day cryptocurrency news and tips!