As reported in the Wall Street Journal, digital currency firm DAO was the victim of a hack in which 3.6 million Ethereum coins, valued at $55 million dollars was removed from the DAO account. According to the article the “attacker appeared to have exploited a loophole that essentially allowed a DAO stakeholder to create an identical fund and move money into it”. There are now published reports that the digital currency firm will cease to exist – which brings to mind the 2012 incident in which Knight Capital lost 440 million dollars due to a failed system upgrade. Financial services need to consider their cyber security and reliability of their systems or risk the consequences of catastrophic loss.