A Credential Stuffing attack is a variant of Brute Force. In these cases, the attacker already has a list of user names, emails and passwords, typically stolen or leaked from a site or service. This list is used to try and access accounts on a different site or service, leaning on the fact that users tend to re-use passwords on multiple services.
Credential stuffing attacks exploit the common practice of password reuse across multiple accounts. Since many users tend to use the same username and password combination for various online services, attackers capitalize on this behavior. By using previously leaked or stolen credentials, they attempt to gain unauthorized access to accounts on different platforms. This type of attack is particularly effective because it bypasses the need to guess passwords, relying instead on the likelihood that a set of credentials is reused.
These attacks are often automated, with attackers using bots to input the stolen credentials into numerous websites at a high speed. This automation allows them to test thousands or even millions of username and password combinations in a relatively short period. The scale and speed of credential stuffing make it a significant threat, as even a small success rate can result in a large number of compromised accounts. This highlights the importance of unique passwords for different online services.
To combat credential stuffing, organizations are increasingly employing multi-factor authentication (MFA), which adds an additional layer of security beyond just the username and password. MFA requires users to provide another form of verification, such as a code sent to their phone or biometric data, making unauthorized access significantly more difficult. Additionally, monitoring for unusual login attempts and implementing rate-limiting can help in detecting and preventing these attacks. Educating users about the importance of using unique passwords for each online account is also crucial in reducing the success rate of credential stuffing attacks.