How to test OTP (one time passwords)

Many applications use OTP one time passwords to secure their data. See how to test OTP using real email addresses.

Nowadays, all of your data is kept online. As a result, unethical hackers might overcome the security barrier and corrupt your data. That is why it is vital to increase security. Businesses are increasingly using multi-factor authentication, which often includes a one-time password as a verification step.

This post will discuss one-time passwords, their advantages, and how to test them in your application.

A description of multi-factor authentication

You may use multi-factor authentication to demonstrate to a system that you are who you say you are with these three categories, something you remember (for example, a password), who you are (for example, your biometrics), or something you already have (e.g., your phone). This is usually known as a two-factor authentication since the majority of multi-factor solutions need just both of these requirements.

What is OTP?

The idea is that it is a passcode intended for one-time use for a specific protected action, albeit in most cases, they aren't really single-use and instead are valid for a very short amount of time (typically between 30 seconds and 2 minutes). Here are different one-time password creation techniques, some of which are patentable. The most common is the Time-based One-time Password (TOTP), which adds the current time into the password generation process.

Why is OTP testing performed?

OTP testing is required to limit the risk of security breaches caused by security system flaws. However, a rigorous testing approach is needed to cover the intricacies of security measures such as one-time passwords. What we foresee is as follows:

  • By testing it, you may ensure that your password matches the format you desire
  • Attempting to determine the password's expiration date. Examine your passwords to check if they expire on time or if they can be used for the proper time.
  • Passwords are being tested for their usefulness. A one-time password should be used to authenticate only one session or transaction.
  • You might also test how your application responds to various OTP queries.

Assume you're using an authenticator app that generates passwords using an algorithm that takes the current time into consideration. This password, also known as a "shared secret," is created independently by the server and the app. A user can only log in if their password matches the password saved on the server.

However, because the generating approach considers time, it is dependent on the server and the app being in sync.

These are all critical considerations while performing OTP testing. Even if you are not implementing and testing the one-time password feature, you may still want to do OTP tests as part of end-to-end testing. For example, if you are testing logins, you must first complete OTP testing.

How to conduct an OTP Test?

One-time passwords are frequently created on the backend and transmitted by email or SMS. But you can use a mobile app to generate them. It is simple to test incoming emails and SMS. But if you feel difficulty in performing OTP testing, you can use online templates for this purpose.

Testing OTP functionality in an application is a little more difficult. One approach would be to build the one-time password mechanism using a Java server library, such as GoogleAuth.

TOTP (time-based one-time paswords) are generated using this library. You could use GoogleAuth to build a secret in your backend service, import the secret using GoogleAuth code, and ensure that the code generates a real TOTP 6-digit number.

The TOTP algorithm is available in a variety of programming languages, including Go, Python, and PHP. Naturally, GitHub is the best place to look for standard implementations in multiple languages; simply search for a phrase like "RFC 6238" and filter results by language.

Email testing libraries

Use a free API service such as MailSlurp to test OTP using disposable email accounts.

Ready to dive in?Start building email applications today.