How does 2FA remain secure when most people have saved passwords or credentials/”remember me” on one single device, usually their smartphone; potentially a single point of failure? For that matter, why only 2FA and not 3 or 5FA?

Question

For clarification, some banking apps simply require a seperate password in a seperate app to be entered, emulating the same concept that Google Authenticator employs.

How is this more secure than say, having a secondary password field in the main app?

In: Technology

Answer 1

> How is this more secure than say, having a secondary password field in the main app?

Because the second “password” isn’t something that you memorize. It’s generated with some very complex math based on a secret “seed” value and the current time. It changes roughly every 30 seconds. If someone doesn’t have access to that secondary app, then they can’t get into the account even if they know your passwords.

>why only 2FA and not 3 or 5FA?

2FA stands for “two-factor authentication”, and there are only three “factors”:

* Something you know (i.e. a password)
* Something you have (i.e. the phone with the 2FA app installed on it)
* Something you are (i.e. biometrics)

You can have 3FA if you have to enter a password that you know, get an auth token from a device that you have, and scan your fingerprint. But 5FA isn’t a thing.