Credential Stuffing: How To Protect Yourself from Attack

In an age where cybersecurity threats loom large, one of the most prevalent attacks facing both individuals and businesses alike is credential stuffing. This malicious technique preys on the unfortunate reality that many people reuse the same usernames and passwords across multiple accounts, creating a vulnerability ripe for exploitation. But fear not, for there are measures one can take to mitigate the risk of these attacks. In this blog post, we will examine the intricacies of credential stuffing, uncovering its methods, dangers, and most importantly, how you can safeguard yourself against it.

What Is Credential Stuffing?

Credential stuffing is a type of cyberattack where hackers use stolen account credentials—typically usernames and passwords—to gain unauthorized access to user accounts on other platforms through large-scale automated login requests. This method exploits the common practice among users of reusing the same login information across multiple websites and services. By leveraging automated scripts, attackers attempt to log in to various websites with the stolen credentials, aiming to breach accounts that use the same username and password combination. This attack is particularly effective because of its simplicity and the vast availability of stolen credentials on the dark web. This approach presents a significant challenge for businesses striving to mitigate fraudulent login attempts as the process yields a lower amount of seemingly routine login attempts rather than a high quantity of failed logins from trying every combination of letters and numbers in most brute force attacks.

How Does Credential Stuffing Work?

To execute this type of attack, cybercriminals add a list of stolen credentials to a program or tool that will automatically try the credentials on multiple sites at once. Once the cybercriminal has found a site that works with the credentials, they will have access to the user’s account and data and will do what they please with the information. Typically, they will sell access to comprised accounts, commit e-commerce fraud, or carry out corporate theft/espionage. Furthermore, once they have breached an account, they will often change the credentials and recovery information where possible to lock out the account’s legitimate owner.

Credential Stuffing Attack Examples

In early October of 2023, 23andMe disclosed a credential stuffing attack where hackers accessed approximately 14,000 accounts by using credentials that were the same as those compromised on other platforms. The attackers did not breach 23andMe’s systems directly, but instead used previously stolen usernames and passwords. The compromised accounts were exploited to gain access to the DNA Relatives and Family Tree features, affecting about 5.5 million and 1.4 million profiles, respectively. These features contain sensitive user information, including display names, the nature of genetic relationships, and limited ancestral data. This incident highlights the risks of password reuse across different services.

Last year, PayPal notified roughly 34,942 users of a credential stuffing attack that occurred on December 6-8, 2022, where hackers accessed accounts using previously compromised usernames and passwords. This attack did not stem from a breach of PayPal's systems, but rather from the reuse of passwords across multiple services. The attackers gained access to personal data including full names, dates of birth, postal addresses, social security numbers, and tax ID numbers, as well as transaction histories and connected payment card details. Although PayPal has no evidence of misuse of the information or unauthorized transactions, they promptly reset passwords for affected accounts and implemented enhanced security measures. Additionally, PayPal offered two years of free identity monitoring through Equifax and advised users to change their passwords and enable two-factor authentication.

How to Prevent Credential Stuffing

To combat these threats, organizations must implement robust, multi-layered credential stuffing protection strategies. Here are essential steps that organizations can take to prevent credential stuffing:

1. Use Advanced Authentication Methods: Implementing multi-factor authentication (MFA) is one of the most effective defenses for preventing credential stuffing. MFA requires users to provide multiple forms of verification before gaining access, which significantly reduces the risk of unauthorized entry.
2. Employ Account Lockout Mechanisms: Set up account lockout policies that temporarily lock out accounts after several failed login attempts. This not only thwarts automated login attempts but also alerts the legitimate user and the organization to potential unauthorized access attempts.
3. Monitor and Throttle Access Attempts: Continuously monitor login patterns and throttle the number of login attempts over a certain period of time or from the same IP address. This can effectively discourage the bulk use of stolen credentials.
4. Leverage IP Blacklisting: Use IP blacklisting to block access from IP addresses known to be sources of malicious activity. Integrating threat intelligence services can help organizations stay updated on the IPs associated with credential stuffing tools and compromised networks.
5. Educate Users About Secure Practices: Regularly educate users on the importance of using unique passwords for different accounts.
6. Deploy Advanced Security Solutions: Utilize security solutions that include capabilities to detect and defend against credential stuffing. These might include using CAPTCHAs, device fingerprinting, and behavior analytics to identify and block suspicious activities.
7. Monitor the Dark Web: Regularly scanning the dark web for leaked credentials can provide early warning signs of potential credential stuffing attacks. Utilizing dark web monitoring tools allows organizations to detect if their user data, such as usernames and passwords, appear in data dumps or are being sold on underground markets. By being proactive in this manner, organizations can prompt users to change compromised credentials before attackers can use them in credential stuffing campaigns, thereby preemptively shutting down potential security breaches.
8. Promote the Use of Password Managers: Advocate for the adoption of password managers among your user base. These tools help individuals and teams manage their credentials more securely. Password managers generate strong, unique passwords for each account and store them in an encrypted format, greatly reducing the chance of password reuse and simplifying the process of maintaining secure access protocols.
9. Enhance Incident Response Plans: Develop and continually update incident response plans to include responses to credential stuffing attacks. Quick and effective action can mitigate damage and restore security swiftly.

By integrating these practices, organizations can not only defend against the immediate threats of credential stuffing but also bolster their overall cybersecurity posture. Credential stuffing attack prevention requires a proactive approach, combining technology, policy, and education to build a resilient defense.

Improving Security Awareness to Combat Credential Stuffing

Building user awareness is essential in mitigating the risk of credential stuffing attacks, which have become increasingly common. Many people still use the same passwords across multiple websites, making it easier for attackers to gain unauthorized access with stolen credentials. At Compass IT Compliance, we have spent the last decade emphasizing the importance of a strong security culture through detailed security awareness training and testing. We have dedicated ourselves to educating organizations and their end users on how to spot and defend against these kinds of threats, encouraging the use of unique passwords and multi-factor authentication to strengthen their defenses.

Our approach at Compass IT Compliance goes beyond immediate fixes. We offer regular workshops and proactive dark web monitoring to stay ahead of potential breaches. We also focus on long-term strategies, such as continuous education on secure password policies and promoting the use of password managers. By combining these robust security measures, Compass IT Compliance ensures that everyone we work with is equipped to face the ever-changing cyber threat landscape, protecting their sensitive information from attackers. Contact us today to learn more and to discuss the unique security threats your organization is facing!