“You don’t think you have this problem? You have this problem,” said Jane Holl Lute, CEO of the Center for Internet Security, at an eye-opening panel at Fortune‘s Most Powerful Women Summit in Washington, D.C. on Tuesday. “We’re all on the same internet, facing the same problems.”

Globally, there were more than 40 million cyber attacks on businesses last year, up nearly 50% from 2013. What’s more, the opportunities for hackers and other bad actors will only grow. Helen Greiner, CEO of drone-maker CyPhy Works, reminded the MPW audience that drone deliveries and driverless cars are on the horizon. “Imagine if they are hacked,” she said.

The possibilities are frightening, but there’s no reason to panic. According to Lute, following the four basic steps of cyber security “hygiene” can head off up to 90% of attacks. All companies and organizations should ask themselves the following questions, she advised:

1. Do we know what is connected to our network? (“The answer is usually no,” said Lute.)

2. Do we know what’s running—or trying to run—on our networks?

3. Do we properly manage the people who have administrative permission to wander around our network? This includes ensuring that employees and administrators are not sharing passwords. (“Would you share you toothbrush?” asked Lute. “Please say, ‘no.'”)

4. Do we have an automatic system that continuously monitors our network?

If the answer to any of the above is a negative, your team should immediately take all required steps to get to “yes.”

Paula Tolliver, corporate VP of Dow Chemical Company (DOW), agreed that these steps are vitally important and noted that companies sometimes make the mistake of investing significant money in other technologies to help defend against cyber attacks before focusing on good hygiene and understanding their own unique threat landscape. “Get the fundamentals right—then advance your tech,” she said.

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