This theft proved that decentralized exchanges are not immune to hacks. The criminals exploited a security flaw in a wallet used to update some of the exchange’s smart contracts. The scheme worked and the hackers made off with millions. In the aftermath of the hack, Bancor was forced to shut down. Ironically, Bancor was one of the most high profile ICOs of 2017. It managed to raise over $153 million in investments during its token sale.