Have you ever heard of sim-jacking?
We hadn't either, until it was brought to our attention by someone who believed they'd been the victim of it.
Adam Ross says he recieved a couple "hang-up" calls on Wednesday night. When he checked his phone the next morning, he saw a text from a number he traced back to his bank. When he tried to log into his account, he couldn't.
A later check with the bank from another phone, revealed $3,000 was missing from his account.
He's since been told by the bank, that he may have been the victim of a hack called sim-jacking. What is it?
"Basically, what they are doing is they are taking your sim card, and they are transfering over to their mobile device. They are doing it to take control of your mobile phone." says cyber security expert Chris Dodunski, from Cyber Hunter Solutions.
"The mobile phone is really the gateway to almost your entire life." says Dodunski, which is why the hackers will take their time with this one.
It doesn't happen overnight, with the theives building a profile of you, and then turning to the mobile phone companies, claiming to be you. That's when they claim they lost their phone and need to transfer information to a new device. That gives them control.
Or, security experts say there could be crooks working on the inside, within the mobile phone companies.
Claudiu Popa, a certified cyber security expert has some advice on how you can protect yourself.
"You should always have a pin number, you use to authenticate yourself when you're calling your phone company."
And he suggests keeping a close eye on your financial accounts to pick up on any irregularities.