Industry Observations-Technical Insight-Vulnerabilities-Web Application Security

Web Security for the Tech Impaired: What is two factor authentication?

You may have heard the term ‘two-factor’ or ‘multi-factor’ authentication. If you haven’t heard of these terms, chances are you’ve experienced this and not even known it. The interesting thing is that two factor authentication is one of the best ways to protect your accounts from being hacked.

So what exactly is it? Well traditional authentication will ask you for your username and password. This is an example of a system that relies on one factor — something you KNOW — as the sole authentication method to your account. If another person knows your username and password they can also login to your account. This is how many account compromises happen, a hacker simply runs through possible passwords of accounts they want to hack and will eventually guess the correct password through what is known as a ‘brute force’ attack.

In two-factor authentication, we take the concept of security a step further. Instead of only relying on something that you KNOW we also rely on something that you HAVE in your possession. You may have already been doing this and not even realized it — have you logged into your bank or credit card only to see a message like ‘This is the first time you have logged in from this machine; we have sent an authentication code to the cell phone number on file for your account — please enter that number and your password” or words to that effect? That is an example of a site that is using two-factor authentication. By using the cell phone number they have on file to send you a text to confirm that you are who you say you are, they are relying on not only something you KNOW but also something you HAVE. If an attacker were to steal or guess your username and password, they would not be able to successfully login to your account because you would receive a text out of the blue for an account you didn’t login to. At that moment you would know someone is probably trying to login to your account.

This system works with anything you have. Text is the primary means of two factor authentication as most people have easy access to a cell phone and it’s easy to read the code to enter onto the site. This system works just as well with a phone call that provides you with a code or with an email. Anything that you HAVE will work with two factor authentication. You may notice that most sites will only ask you for this information once; typically sites will ask you the very first time you log in from a given device (be it mobile, desktop or tablet). After that, the site will remember what devices you’ve signed on with and allow those devices to login without requiring the second factor, the auth code. If you typically log in with your home computer, and then remember you need to check your balance at work, the site will ask you to log in with two-factor authentication because it does not recognize that device. The thought is that a hacker is unlikely to hack into your account by breaking into your house and using your own computer to login.

Now you may be saying ‘that sounds great! Where do I sign up?’. Unfortunately not all systems support two factor authentication. However, the industry is slowly progressing that way. Sometimes it isn’t enabled by default but is an options in a ‘settings’ or ‘account’ menu on the site. To see a list of common sites and status on supporting two-factor auth, is a great resource. I highly recommend turning this service on for any account that supports it. Typically, it’s extremely quick and easy to do and will make your accounts far more secure then ever before.

Tags: web security