Think two-factor authentication for your financial accounts and a passcode on your phone protects you from hackers?

Think again…

SIM hijacking could allow criminals to access your money

In a new scam that's generically being called "mobile hacking" and more accurately termed "SIM hijacking," BuzzFeed reports criminals are now able to breach your financial accounts with as little as the last four digits of your Social Security number.

Here’s how this one plays out: A crook who has the last four of your Social can call your wireless carrier and impersonate you. They can convince the customer rep to issue a new SIM card for your phone number, which they can then activate to take control of your number.

Once your new phone number is in their control, they can gain access to your accounts — bank and investment accounts, as well as social media and email accounts — and siphon money out without your knowledge.

Mind you, this isn’t just paranoid speculation about the latest iteration of hack attacks coming down the line.

No, this is happening right now in real time! That's according to this report from Motherboard that includes nine personal tales from people who have been affected by SIM hijacking.

The moral of the story here is don’t assume you’re protected with just a passcode on your phone and standard two-factor authentication on all your accounts. While that’s a good start, it’s increasingly not enough.

The best way to fight back is to add a PIN to your smartphone account, which creates a necessary third layer of protection.

The procedure to do this varies by wireless carrier:

AT&T

You’ll have to log into your AT&T account to add a PIN. Once you’re in your account, go to “View Profile” and then navigate to “Sign-in Info.”

Then look for “Wireless Passcode.” Finally, select “Manage Extra Security” to create your new passcode.

Sprint

Sprint requires its customers to have a PIN. It’s a good idea to periodically update yours by logging into your account.

Once you’re in, select “My Sprint” and then “Profile,” followed by “Security.” Scroll down to “Security Information” to update your PIN. Be sure to hit “Save” before exiting.

T-Mobile

Dial either 611 or 1-800-937-8997 on your phone to add a PIN to your phone’s account. Unlike the other carriers which only allow four digit PINs, T-Mobile allows you to create a six-digit passcode.