Over the last week, a massive ransomware attack with the moniker WannaCry impacted tens of thousands of computers around the world. This cyberattack disrupted organizations as diverse as hospitals in the UK, auto maker Renault in France, and FedEx in the United States.

Now the fingerpointing begins – and there’s plenty of blame to go around. Top of the list are the criminals themselves, of course: a hacking group that calls themselves the ‘Shadow Brokers.’

The blame doesn’t end there, however. Researchers credit the NSA for creating and weaponizing the ransomware code in the first place. And then there are the folks who stole the code from the NSA – who may or may not be the same people as the Shadow Brokers.

None of these attacks would have been successful, however, if it weren’t for additional culpable parties: IT administrators around the world who simply failed to install a two-month-old software patch from Microsoft.

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