Credential Stuffing-What Is It and How Do You Prevent It?

Credential stuffing cases have been on the increase lately. The chances are that you have heard of various instances on the mainstream media and social networks. Several online accounts have been taken over in droves, but companies insist that it is not their fault. Although this can be maddening, the reality is that it is not their fault. The real culprit of this frustrating menace is a technique referred to as credential stuffing. Read on to learn more about credential stuffing.

What is Credential Stuffing?

Credential stuffing is a hacker technique where cyber criminals obtain your credentials from an online service and attempt to log in to your other online accounts using those credentials. To help you understand, the cybercriminals may use your Facebook username and password to log in to your PayPal account using the same credentials. The attackers hope that you are using the same credentials across your online accounts.

After obtaining the credentials, the attackers are trading and selling them on the black market. Unfortunately, this vice is quickly getting out of hand since attackers are now using advanced tools, including bots, to get around security measures.

Although this type of brute attack has a 0.1% chance of success, the ever-increasing amount of credentials being traded in the black market means you cannot dismiss credential stuffing just yet. Case in point, attackers manage to obtain authentic credentials for every thousand online sites they attack. If the breached account contains one million credentials, the attackers will obtain 1,000 sets of credentials. The breached credentials might contain a sheer amount of profitable data, including credit card numbers and sensitive data. Attackers can then use the data in phishing attacks. Above all, they can use the data to gain access to other online services.

What is more, technological advancement also makes it a viable attack. Attackers are using advanced tools like bots to overcome the protections. These bots slow down the login process to capture the credentials. Besides, cyber stuffing is indistinguishable from normal login traffic. That is why victimized online services providers fail to identify these attacks. Even if the company tried to stop the attack, they would have trouble identifying legitimate log-in attempts.

Another reason why credential stuffing is effective is that most people reuse passwords. According to recent studies, more than 85% of users reuse the same password across all their online accounts.

Credential Stuffing VS. Brute Force Attacks: What is the Difference?

While credential stuffing is a type of brute force attack, the two are very different. In perspective, attackers try to guess the passwords with no clues during a brute force attack; they use breached data during a credential stuffing attack.

Besides, you can easily prevent brute force attacks by using a strong password. Use a combination of numbers, uppercase letters, and special characters to create a strong password. However, a strong password cannot stop credential stuffing on its own. You will have to use other measures to prevent credential stuffing. Keep reading to discover how you can protect yourself from credential stuffing.

1. Use Strong and Unique Passwords

One of the best ways of preventing credential stuffing attacks is to use strong and unique passwords. As a site administrator, you can encourage your users to set strong passwords for each account. Strong passwords should contain more than ten characters and should combine lowercase and uppercase letters, special characters, and numbers. Site owners can also use password manager solutions and password randomizers to help users set unique and strong passwords.

2. Take Advantage of Multi-Factor Authentication

Multi-Factor Authentication or MFA seeks to ask for additional information apart from the typical username and password. This means the attacker will have to provide the additional information even after using the correct credentials. The additional information can be:

  • A valuable item.
  • An additional password.
  • Face ID.
  • Fingerprints.
  • Iris.

Although MFA effectively stops brute force attacks and credential stuffing, too many MFA requests can be overwhelming. That is why site administrators should find the best balance to guarantee optimum user experience. A good balance will also reduce the bounce rate. The following are some of the instances that require MFA:

  • When a different browser, IP address, signature, and device are used for logging in.
  • Suspicious login attempts from unusual locations.
  • Scripted activities.
  • Suspicious IP address.


Attackers use bots during brute force attacks and credential stuffing. The best way of stopping these bots is to implement CAPTCHA. However, this technique should be used with other measures for various reasons, including:

  • Attackers use farm services to get around CAPTCHA.
  • It can also ruin the user experience.

4. Warn Users Immediately You Detect Unusual Activity

Several users are not aware when their online accounts are compromised. That is why you should get in touch with the users immediately when you detect suspicious activity. Like the other techniques, sending too many notifications can overwhelm your users. Only send important notifications to improve user experience.

It is also advisable to let your users view the recent login activity. Moreover, let the users know about all the active sessions if your application allows multiple sessions.

5. Utilize Fingerprinting Solutions

Fingerprinting allows you to confirm the user’s authenticity by checking the browser’s legitimacy, device, operating system, the language used, and browser. Using this method, you should ask the user to provide additional information if the new traffic fails to match the previous signature. Fingerprinting also allows users to track login success ratios to prevent credential stuffing.

6. Use Bot Detection Solutions

Investing in a bot detection solution is also an effective way of preventing credential stuffing attacks. Advanced credential stuffing mitigation solutions will detect a malicious bot and stop it in real-time.

Final Thoughts

Stopping credential stuffing is not an easy task. The good news is that you can use these six methods to prevent and stop credential stuffing in real-time. Using advanced bot protection solutions can save you time and money while improving the user experience. All you have to do is to choose the ideal solution.