When we sign up for new accounts online, sites would usually ask us for our mobile numbers as a means of adding an extra layer of security such as with Google's two-factor authentication, a feature present in many other platforms like Apple and Facebook, in which the site will send you a text message indicating a code you need to input in order for you to log onto the platform.
Despite that, there are potential risks involved with giving out our phone numbers so we need to assess whether the benefits that we will receive would be greater than the risks involved. The New York Times tech columnist Brian Chen asked security researchers to show him what kinds of information will be exposed just by sharing his phone number. And it's astonishing how much they were able to find.
In fact, your phone number may have now become an even stronger identifier than your full name. I recently found this out firsthand when I asked Fyde, a mobile security firm in Palo Alto, Calif., to use my digits to demonstrate the potential risks of sharing a phone number.
Emre Tezisci, a security researcher at Fyde with a background in telecommunications, took on the task with gusto. He and I had never met or talked. He quickly plugged my cellphone number into a public records directory. Soon, he had a full dossier on me — including my name and birth date, my address, the property taxes I pay and the names of members of my family.
With just one's phone number, any hacker could access these information and use that to log onto our accounts and bypass the security questions. More than that, it is also possible for them to pose physical threats, for instance, by going to our home addresses and compromising our security or threatening harm upon us or our family members.
But in our hyperconnected world, we cannot avoid giving out our phone numbers. However, there are instances when it is safe to share phone numbers. To learn more about them, check out Brian Chen's article on The New York Times.