This is Planet Money from NPR.

In December of last year, somebody at a cybersecurity company, a company called FireI,

noticed something just a tiny bit out of the ordinary.

Somebody was logging into the company's system using an employee's username and login,

but they were using a different phone number than the employee had used before.

So people get new phone numbers, that's not the big deal.

This particular company, though, FireI, is in the computer security business.

So they take this kind of thing really seriously.

So one of our staff members called the person, whose account was used and said, hey, did

you register a second phone?

That's Kevin Mandia, the CEO of FireI.

And the gentleman said, no, I did not register that phone.

So who did?

Who indeed?

Yeah, well, so Mandia and his team at FireI, they start trying to figure out exactly that.

How did some random person get into their network and end up registering a new phone?

And the more they learned, the more worried Mandia got.

It just felt like the breach that I was always worried about.

We didn't know a lot at the time.

It just felt like it was time to brace for impact.

Hello, and welcome to Planet Money.

I'm Jacob Goldstein.

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