Being a crucial part of the account takeover process (ATO) credential stuffing tests stolen credentials. It is considerably more precise than a brute force attack.

Credential stuffing abuses the most sensitive gateways of your website, such as the login and payment page.

With bot's evolution, these attacks are getting more recurrent and sophisticated. Credential stuffing causes reputation and funding loss. It hurts online businesses by affecting customer lifetime value, reputation, and revenues.

How to prevent credential stuffing and provide the best security to your website?

Credential Stuffing Definition

Credential stuffing: an automated process of filing login and password for fraudsters to gain access to user accounts. Credential stuffing is a form of brute force attacks and a popular method of account takeover.

How Credential Stuffing Works

  • Fraudsters get login and password using data breach, phishing, social engineering, skimming scripts, or other methods.

  • Bots submit a vast number of obtained credentials on website gateways until they manage to enter an existing account.

  • The account with the right credentials gets stolen and used for fraudulent purposes - spam, unauthorized purchases, etc. Credential Stuffing List - a free, open-source, anonymous hosting service that found out a large amount of personal data on its servers.

The data turned out to be lists of credentials to use for credential stuffing and further ATO attacks. Later on, the platform submitted them to cybersecurity experts.

Credential Stuffing Tools











Is Credential Stuffing a Data Breach?

Technically, credential stuffing is not a data breach per se. The process itself does not involve hacking databases to get the information.

Credential stuffing is the aftermath of a data breach. The breached data falls into the wrong hands and is used to gain access to user accounts.

Credential Stuffing and GDPR

However, General Data Protection Regulation or GDPR, a regulation in EU law concerning personal data protection and privacy states:

“a breach of security leading to the accidental or unlawful destruction, loss, alteration, unauthorized disclosure of, or access to, personal data transmitted, stored or otherwise processed” is considered a personal data breach.

Thus credential stuffing is regarded as a personal data breach in the EU and must be reported accordingly.

Credential Stuffing vs. Password Spraying

Credential stuffing and password spraying are very similar by nature. The only difference is in password spraying.

They use several passwords for trying to get access to websites. In the case of credential stuffing, it is one credential used in different websites.

Credential Stuffing vs. Brute Force

Credential stuffing is considered one of the forms of brute force attacks. Nevertheless, they do have differences.

Brute force is an attempt to guess passwords without any data input, hints, or clues. Its basic random usage of letters, numbers, and symbols is often combined with common password samples.

Credential stuffing uses already obtained clear data, which reduces the number of possible variations to just one.

Credential Stuffing vs. Credential Harvesting

Credential harvesting utilizes MITM attacks, DNS poisoning, phishing, social engineering, and other methods to obtain a large number of account credentials. After that, fraudsters can proceed to credential stuffing.

How to Avoid Credential Stuffing

Since credential stuffing is a bot-operated attack, there are only two options in avoiding it:

  • Advanced AI-based CAPTCHA with behavioral and environmental analysis will detect bot features at sensitive website gateways instantly and will not let bots proceed with the attack.

  • Full-stack bot management solution that possesses similar characteristics but works on all website gateways and costs much more.

How to Detect Credential Stuffing

Credential stuffing is normally conducted in a very slow and secret manner so it is hard to detect, it is characterized by:

  • Frequently failed logins and lockouts;

  • Unexplained traffic spikes on the login page;

  • Increased customer complaints on unauthorized access;

How to Stop Credential Stuffing

Credential stuffing mitigation is a complex process that requires powerful solutions in the bot management industry such as:

Full-stack bot management solutions

Bot management solutions allow you to detect and mitigate bots at all website entries. However, this solution is quite pricy.


2-factor authentication or multi-factor authentication is a good solution. It adds another layer of verification except for login credentials, such as SMS code, e-mail code, or a fingerprint for a mobile application, which is hard to imitate for bots.

However, the e-mail code option may not work if the ATO attack compromises the e-mail, and you haven't set up backup mail.

Advanced CAPTCHA

Advanced AI-based CAPTCHA is one of the strongest fighters against account takeover attacks. Its behavioral analysis, environmental analysis, and the least user friction provide the most effective solution against bot attacks.


Why are we telling you all of this?

Well, because credential stuffing prevention is vital for your reputation, revenue, and, consequently, your business growth. Ignoring this issue is dangerous both for you and your customers.

Credential stuffing is a part of the account takeover process. Having these issues at hand urges you to provide better security for your website or application and choose safety measures at once.

Protecting your website gateways with strong security solutions will save your customers from hackers and bot attacks and provide the best user experience.

GeeTest provides a high-security level to both websites and applications using environmental and behavioral recognition systems to detect and mitigate bots with the least user friction providing the best user experience in the process.

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