MINNEAPOLIS (CBS Local) -- Have you ever gotten a phone call from your own number? Or one that was just a few digits off? It's the latest illegal scam to get you to answer your phone – neighborhood spoofing.
The calls had Jeanne from Hastings and Sandy from Willmar wanting to know: How do they even do that?
"In order to understand spoofing, it's important to understand the phone network isn't a single network," says Chris Schulte, a cybersecurity expert and Director of Information Security with Enterprise Knowledge Partners, LLC.
Instead, it's several different networks with a number of different technologies, including the internet.
"Because the telephone network is very open, that allows scammers and telemarketers and spammers to tap into that network," Schulte says.
Caller ID spoofing itself is not illegal.
Companies have been doing it for a long time when they have all the phone lines from one building show up as the company's main number. But, what is illegal is caller ID spoofing with the intent of committing a fraudulent act.
Right now, the FCC rules specifically require that a telemarketer to transmit or display its telephone number and, if possible, its name or the name of the company for which it is selling products or services.
It also requires the display of a telephone number someone can call during regular business hours to ask to no longer be called.
According to Schulte, 99.99 percent of calls where the caller ID has been spoofed are illegitimate.
"They're essentially using software that routes their phone system," he says.
In a 20-second demonstration, Schulte showed how to spoof a phone call from an app he downloaded from the Apple app store.
He entered the number he wanted to call and the number he wanted to display into the app and hit send. Within five seconds, the call was made.
What happened was Schulte had his phone call the service through the app. That service then used its connection into the phone network to spoof the caller ID.
Spoofing operations can range from a single person at home using an app on their phone to a large business designed to be a call center. Often times, those operate illegally outside of the U.S.
Schulte says stopping these illegal calls isn't as easy as the government cracking down. He believes there also needs to be changes to the laws and technology.
But, until then, the FCC says: Don't answer these calls. If you do answer, don't press any numbers and just hang up.
You can also register your phone number on the government's Do Not Call list.
The Federal Trade Commission also recommends installing a robocall blocking app on your phone.
[H/T CBS Minnesota]
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