What is Credential Stuffing?

Credential Stuffing Explained

Credential stuffing is a cyber attack technique that exploits the common practice of reusing the same username and password combinations across multiple websites and services. The attack relies on leaked or stolen credentials, which are typically obtained from previous data breaches or other sources. Cybercriminals aim to use these credentials to gain unauthorized access to user accounts, potentially leading to identity theft, financial fraud, or further security breaches.

How does Credential Stuffing work?

The primary method employed in credential stuffing attacks involves the use of automated tools or bots, which systematically attempt login requests with various combinations of usernames and passwords. These tools can send thousands of login requests per second, allowing attackers to quickly test a large number of credential combinations against a target website or service. Attackers often use proxies or botnets to distribute the login attempts, making it harder for the targeted systems to detect and block the attack based on IP addresses.

When the credential stuffing attack successfully matches a reused username and password combination, the attacker gains unauthorized access to the user's account. They can then use the compromised account for various malicious purposes, such as conducting fraudulent transactions, stealing personal information, or spreading spam and malware. In some cases, attackers may also attempt to leverage the gained access to compromise additional accounts or infiltrate the targeted organization's network.

What is the Cost of Credential Stuffing?

The cost of credential stuffing can be substantial, both in terms of direct financial losses and the broader impact on the reputation and trustworthiness of affected organizations. The financial losses can arise from various sources, such as fraud, unauthorized purchases, or the loss of valuable customer data. Moreover, companies may face regulatory fines for failing to protect customer information adequately. In addition to these tangible costs, credential-stuffing attacks can lead to a loss of trust among customers and users, potentially resulting in reduced user engagement and business opportunities.

Credential Stuffing vs. Brute Force Attacks

Credential stuffing and brute force attacks are both methods employed by cybercriminals to gain unauthorized access to user accounts. While they share a common goal, they differ significantly in their approach, techniques, and the resources required.

Credential stuffing attacks involve using previously leaked or stolen credentials—usually sourced from data breaches—to attempt unauthorized logins on various websites and services.

On the other hand, brute force attacks entail systematically guessing a user's password through trial and error. In these attacks, the cybercriminal does not rely on previously obtained credentials. Instead, they use automated tools to generate and test a vast number of possible password combinations, typically starting with the most common or weak passwords. Brute force attacks can target individual accounts or attempt to gain access to multiple accounts on a specific platform. These attacks can be time-consuming and resource-intensive, especially when targeting accounts with strong, complex passwords.

Both types of attacks pose significant risks to user accounts, underlining the importance of adopting strong, unique passwords and implementing advanced security measures to protect against unauthorized access.

How to Protect Against Credential Stuffing

To protect against these attacks, organizations must adopt a multi-layered approach that incorporates various security measures and technologies. This article will discuss some key strategies for protecting against credential stuffing, including passwordless authentication, continuous authentication, multi-factor authentication (MFA), breached password protection, and credential hashing.

Passwordless Authentication

Passwordless authentication is a security method that eliminates the need for traditional usernames and passwords, thus reducing the risk of credential stuffing attacks. Instead of relying on passwords, passwordless authentication utilizes other factors, such as biometrics (e.g., fingerprint, facial recognition) or one-time codes sent via email or SMS. By eliminating passwords, passwordless authentication removes the primary target of credential stuffing attacks.

Continuous Authentication

Continuous authentication is a security approach that constantly verifies users' identities throughout their sessions rather than only at login. This can be achieved through various techniques, such as behavioral biometrics (e.g., keystroke patterns, mouse movements), time-based analysis, or ongoing verification of other factors (e.g., location, device). Continuous authentication helps protect against credential stuffing by quickly detecting and responding to unauthorized access attempts, even if the attacker bypasses the initial login process.

Multi-Factor Authentication (MFA)

MFA requires users to provide two or more independent factors to verify their identity during the authentication process. These factors can include something the user knows (e.g., a password), something the user has (e.g., a hardware token), or something the user is (e.g., biometrics). By requiring multiple verification methods, MFA makes it more challenging for attackers.

Breach Password Protection

Breach password protection is a proactive approach to securing user accounts by monitoring and blocking the use of known compromised passwords. This can be achieved by cross-referencing user passwords with databases of known breached credentials. If a user attempts to set or reset their password to a known compromised password, the system will prompt them to choose a different, more secure password. This measure helps to prevent attackers from successfully using stolen credentials in credential stuffing attacks.

Credential Hashing

Credential hashing is a security practice that involves storing hashed versions of passwords rather than plain text passwords in databases. Hashing is a cryptographic process that transforms a password into a fixed-length string of characters. This transformation is designed to be irreversible, meaning it is computationally infeasible to determine the original password from the hashed version. When a user logs in, the system hashes the submitted password and compares it to the stored hashed version. If the hashes match, the authentication is successful.

In the event of a data breach, hashed passwords are much less useful to attackers than plain text passwords. However, attackers may still attempt to crack the hashes using techniques like rainbow table attacks or brute force attacks. To further strengthen password hashing, organizations should also employ techniques such as salting (adding a random value to the password before hashing) and using modern, computationally-intensive hashing algorithms like bcrypt, Argon2, or scrypt.

In conclusion, credential stuffing is a pervasive cybersecurity threat that exploits the widespread issue of password reuse, targeting both individuals and organizations. As cybercriminals continue to employ this attack method, it becomes increasingly vital to prioritize the implementation of robust prevention tactics.

Learn more about IRONSCALES enterprise-grade account takeover prevention here.