If you’ve ever put your mobile number on your Facebook profile – something FB is keen for you to do if you upload pictures from mobile – you should worry.
The simple reason is that people can search for you using your number, as soon as you add it to your profile.
Want to see it for yourself?
Try entering any random phone number (with ISD code) on to the search bar in Facebook. If anyone has added that phone number to his Facebook account, you can easily see that person’s name, picture and location – regardless of their privacy settings.
With 1.5 billion active users the chances of finding real persons from random numbers is very high. Unfortunately, most users are not even aware they are ‘sharing’ their personal details by adding phone numbers.
The dangers of online data sharing
The names, locations and personal photographs of millions of users could be harvested by hackers, allowing them to gather an enormous database of Facebook users to sell on black markets, simply by randomly guessing a mass number of users’ phone numbers at any one time.
The cyber criminals’ black market has become even more profitable than the illegal drug trade, according to a report last year by the national security division of RAND Corporation.
Pictures, names, phone numbers, education history, and locations can be sold on a network of illegal trading sites, the report found. Typically, hackers sell vast quantities of data in bulk for an astonishing profit.
Twitter and Facebook accounts are now more profitable than stolen credit cards, according to the report.
Software engineer Reza Moaiandin showed off how he could come up with people’s names and pictures, just using randomly generated mobile numbers.
Moaiandin said the leaky information is the equivalent of, ‘walking into a bank, asking for a few thousand customers’ personal information based on their account number, and the bank telling you: “Here are their customer details.”
If you’re worried, here’s how to remove your phone number.