Cybereason Senior Director Of Intelligence Services: 'Assume That You're Already Compromised'

"A lot of companies don't really know what their crown jewels are, so to speak. It is really hard for them to answer in a concise sentence which data would cause a business-ending event if stolen, and which assets ought to be monitored closely," said Ross Rustici, senior director of intelligence services at Cybereason.

He explained that it is rare to see the process of a big hack play out in a public setting, with a back and forth between the hackers and the business at risk.

"A lot of companies should be looking at this as a warning to consider what actually happens once the breach hits," said Rustici.

Unfortunately, HBO, which suffered a data breach in early August, has had to take a close look at its most important assets. Rustici urged companies to focus on designating those assets before they are at risk, as well as determining the most efficient, all-encompassing way to defend them.

"Not only is this a technology discussion of 'here's the latest firewall or detection capability', but it is an active hunting perspective. You should really assume you've been hacked so that you can find the activity before it actually gets to your most prized assets."