What is Credential Stuffing and What Organizations Must Do to Protect Against It

What is Credential Stuffing?

A credential stuffing attack is where malicious agents use automatic tools to log in to websites with stolen credentials.

These credentials are usually harvested from previous data breaches or attacks, with cybercriminals often taking advantage of the fact that many people reuse their usernames and passwords across multiple platforms.

There are many ways that hackers seek to benefit from credential stuffing, from financial gain to gaining access to an organization’s most sensitive data.

With this type of attack on the increase, no business can afford to ignore the risk, which can severely impact an organization’s reputation and bottom line, and even result in a hefty regulatory fine.

How Credential Stuffing Works?

In a credential stuffing attack, cybercriminals use nefariously obtained username and password pairs, exploiting password reuse by testing them on multiple sites. Rather than simply guessing passwords, these attacks use known credentials to make their chance of success significantly more likely.

With malicious bots or automated software flooding the target platform with login attempts, this can also cause real issues in terms of website performance, potentially even resulting in downtime, severely impacting legitimate users’ experience.

An attack typically unfolds like this:

• Cybercriminals get hold of stolen passwords and usernames, usually by a previous hacking attack or by purchasing these pairs on the dark web.
• The stolen username and password pairs are fed into bots and automated software to magnify the impact and scale of the attack.
• These bots try the pairs on various website login forms, in an attempt to find matches.
• If a login is successful, cybercrooks steal data (such as financial information or sensitive business data) for use in future attacks or for profit. 

The Business Impact of Credential Stuffing Attacks

Credential stuffing attacks can be devastating for both businesses and individuals. In terms of the latter, a cybercriminal gaining access to their online accounts can lead to financial losses and identity theft, and constitute a serious breach of privacy.

And it may not end with the original attack. A person’s log-in credentials or other personal information could be sold on the dark web, putting them at significant risk of further attack.

For businesses and organizations, a credential stuffing attack also represents a serious threat, often resulting in financial loss or compromising sensitive information. As well as data breaches, it can result in regulatory penalties, reputational damage, and loss of customer trust.

As credential stuffing attacks involve a huge number of login attempts in a short time, they place a heavy burden on IT infrastructure, leading to denial of service or system slowdowns, both of which impact the customer experience.

Should an attack occur, the cost of putting things right, and maybe even paying a regulatory fine, is often extremely costly.

Software to Prevent Credential Stuffing Attacks

An essential part of defending against credential stuffing attacks is deploying the right software to automatically monitor for and fight off threats. The options below offer high-quality protection.

Credential Stuffing vs Brute Force vs Password Spraying Attacks

Brute force attacks also involve malicious agents attempting to gain unauthorized account access, but use a different method from credential stuffing.

In a brute force attack, automated software is typically used to simply throw every possible combination of user names and passwords at a log-in page, operating on the idea that, with enough guesses, the law of averages says one will be right.

As this type of attack necessitates a huge volume of login attempts, it’s more likely to trigger security measures, such as rate limiting or lockout.

Similar, too, to credential stuffing is password spraying, which can be equally difficult to detect. It involves using a few commonly used passwords (like welcome1 or password123) across multiple accounts in an attempt to gain access.

As each account only registers a few attempts at log-in, password spraying attacks frequently go unnoticed – until an account is cracked and, by then, the damage has usually already been done. This approach relies on the assumption that a significant number of people use common, weak passwords.

Why are Credential Stuffing Attacks on the Rise?

In recent years, the number of credential stuffing attacks has been spiking. Incredibly, one in five log-in attempts is thought to be attempted by bots, which underlines the serious nature of the threat and why it can’t be ignored.

A 2023 report found that almost 61 billion credential stuffing attempts were made during an eighteen-month period, with 81% of hacking-related data breaches involving the use of stolen credentials. There are several key reasons that credential stuffing attacks are on the rise right now:

• Botnets have made credential stuffing infinitely more scalable and much more challenging to detect.
• People often reuse login credentials across multiple accounts. And as the average person’s digital footprint grows, so does the number of online accounts they’re likely to have.
• This type of attack is typically low-cost to cybercriminals, but can result in a huge payoff.
• The use of social media and the rise of homeworking have meant that more of an individual’s life is online, with the average person using more apps than ever before.

Easy Steps to Guard Against Credential Stuffing

There are plenty of easy steps a business can take to help deter credential-stuffing cybercrooks. These include:

Deploying Multi-Factor Authentication

Adding an all-important layer of protection to log-in pages, multi-factor authentication (MFA) acts as an extra barrier, after a user has entered their username and password. This could be in the form of a biometric fingerprint check or a one-time password sent as an email or SMS.

Considering Passwordless Authentication

By getting rid of password authentication, you could effectively guard against credential stuffing attacks. Instead of a password, users are verified by, for example, their device, biometrics, or a security key.

Trying Password Hashing

Before storing passwords in their databases, businesses could use password hashing to scramble the passwords. While this won’t prevent password decryption or theft, it gives users more time to alter their passwords should their credentials be compromised.

Using ReCAPTCHA

ReCAPTCHA challenges involve solving puzzles and can prevent bots from submitting login attempts – these puzzles are easy for humans to solve but very hard for bots to crack. They’re a good way to help lessen the likelihood of a credential stuffing attack.

Looking Out for Red Flags

It’s a good idea to keep an eye out for suspicious activity on your login page. This could mean multiple login attempts from a single source in a short time. Putting rate limiting in place can defend against this.

Take Action Today to Protect Your Business from Credential Stuffing Attacks

Credential stuffing attacks may not be as well-known as other cyberthreats, such as phishing, but pose a huge risk to businesses, organizations, and individuals, and the frequency of these attacks is increasing. To best protect your business, it’s vital to deploy specialist software, such as the options we’ve listed above.

Combining these with some common-sense steps, such as using multi-factor authentication and keeping an eye out for red flag user activities, will keep your organization as safe as possible from credential stuffing attacks and many other digital threats.