How Retailers Can Prevent Credential Stuffing Attacks

Introduction

Retailers face a growing cyber threat that strikes every sector of e-commerce and online retail. Credential stuffing has become one of the most damaging forms of attack against businesses that rely on customer accounts. As online transactions and loyalty programmes expand, so do the risks associated with stolen passwords.

This blog is written for retail leaders, IT managers, cybersecurity professionals, and anyone responsible for protecting customer data. The aim is to explain credential stuffing in clear terms, describe how attackers use stolen information, and outline practical ways to prevent it.

Credential stuffing is when attackers use stolen usernames and passwords obtained from previous breaches to access other accounts. Because many people reuse the same login details across multiple platforms, a single breach on one website often exposes accounts elsewhere. Attackers use automated tools to test thousands of credentials rapidly. Once they find a match, they gain access to sensitive customer data or financial information.

The problem has become more urgent as global data breaches continue to rise. According to Verizon’s 2024 Data Breach Investigations Report, over 80 per cent of web application breaches involve stolen credentials. Retailers are frequent targets because they process payment information, personal data, and loyalty points. Attackers view these assets as quick financial gain.

Retail businesses must act decisively to defend against credential stuffing. The cost of inaction includes financial loss, damage to brand trust, and legal exposure under data protection laws.

Understanding Credential Stuffing

Credential stuffing is a type of brute-force attack, but instead of guessing passwords, attackers use valid credentials leaked from other sources. They often purchase these credentials on underground marketplaces or extract them from previous breaches.

Once they have lists of usernames and passwords, they use automated bots to test combinations across different platforms. The bots operate at high speed, sending requests to login pages until they find matches. When successful, attackers gain control of user accounts, which they exploit to steal data, make fraudulent purchases, or resell access.

This technique works because many users reuse passwords across multiple services. For example, someone who uses the same password for a shopping account and an email account risks exposure if either one is compromised. Attackers rely on this predictable human behaviour.

Retailers face unique exposure. Their websites and mobile applications often include user accounts that store payment details and addresses. Many customers also connect multiple services through single sign-on (SSO) or social media accounts, which increases potential attack routes.

Cybergen advises that understanding how credential stuffing operates is the first step to prevention. Once you know the mechanics of these attacks, you can design controls that make them ineffective.

The Growing Risk for Retailers

Online retail is built around convenience. Customers expect quick access, stored payment details, and saved order histories. These same conveniences make systems attractive to attackers. The more customer accounts you hold, the greater your potential exposure.

The British Retail Consortium reported in 2023 that retail remains one of the most targeted industries for cybercrime. Credential stuffing attacks increased by over 40 per cent across e-commerce sites within a single year. Attackers take advantage of high login volumes to mask their activity among legitimate traffic.

Even small retailers face the same level of risk. Automation tools make attacks inexpensive and scalable. A single compromised customer account can provide access to saved payment cards, stored vouchers, or loyalty points, all of which can be exploited for financial gain.

Larger retail platforms suffer even greater consequences. Public breaches reduce consumer confidence, harm stock value, and invite regulatory scrutiny. The reputational damage often exceeds the direct cost of the breach itself.

Failure to address credential stuffing also affects compliance. Under GDPR, businesses must protect user data through appropriate security measures. Ignoring these threats risks fines and legal liability.

Cybergen recommends proactive monitoring and layered security to reduce exposure. Retailers must treat credential stuffing as a business-critical risk rather than an occasional nuisance.

How Credential Stuffing Attacks Work

Attackers follow a predictable pattern. Understanding each stage helps identify where to intervene.

First, attackers collect credentials from public breaches or underground data markets. These lists often contain millions of combinations.

Next, they use automated tools known as bots to test these credentials on target websites. Each bot attempts multiple logins using different usernames and passwords. The volume is high enough to identify matches even if the success rate is small.

Attackers often disguise this traffic through proxy networks or distributed IP addresses to avoid detection. When credentials match, they gain access to accounts. From there, they can extract personal information, perform fraudulent transactions, or resell access.

They also use compromised accounts to conduct further fraud, such as ordering goods for resale, using stored payment methods, or changing contact details to prevent users from noticing.

The automation makes these attacks efficient and low-cost. A single attacker can test millions of login attempts across multiple retail sites in a few hours.

Detection becomes difficult because login attempts appear similar to normal customer activity. This is why many businesses fail to notice credential stuffing until after damage has occurred.

Consequences of Ignoring Credential Stuffing

Retailers who fail to address this threat face several layers of damage.

The most immediate is financial loss. Attackers often use compromised accounts to make purchases or redeem loyalty points. Refund processes and chargebacks add further cost.

Reputational harm follows quickly. Customers who experience account takeovers lose trust in the brand. They associate the breach with poor security, even if the original credentials came from another source.

Operational disruption is another factor. Responding to credential stuffing requires time, investigation, and system recovery. Customer service teams become overwhelmed with account recovery requests, which reduces efficiency.

Legal implications under GDPR are significant. Regulators expect businesses to implement adequate protection against known threats. Credential stuffing is a recognised risk, so failure to mitigate it may lead to penalties.

In 2022, a major UK retailer suffered a large-scale credential stuffing attack that affected over 200,000 customer accounts. Attackers used previously leaked passwords to access accounts, change delivery addresses, and make unauthorised purchases. The brand suffered substantial loss of trust and had to rebuild its online reputation.

Such incidents highlight why prevention is essential. Once customer trust is lost, recovery takes years.

Strengthening Authentication

Strong authentication is the most effective defence against credential stuffing. Retailers should eliminate reliance on single-factor authentication and adopt multi-factor authentication (MFA) across all user accounts.

MFA adds an extra layer of verification beyond passwords. This might include a one-time code sent by text or an authentication app. Even if attackers have the correct password, they cannot log in without the second factor.

Cybergen recommends encouraging all customers to enable MFA and making it mandatory for administrative or high-value accounts. Staff access should also require MFA to prevent unauthorised internal access.

Password hygiene is equally important. Encourage users to create unique passwords for each account. Implement password policies that reject commonly used or breached credentials. Use real-time checks against compromised password databases.

Retailers should also implement account lockout thresholds and CAPTCHA challenges after repeated failed login attempts. These measures slow down automated attacks and signal suspicious activity.

Authentication security should extend to APIs and mobile applications. Attackers often target these systems because they bypass web-based login controls. Implement consistent security across all platforms.

Cybergen offers advisory services to help organisations strengthen authentication frameworks and reduce credential exposure.

Monitoring and Detection

Detection is vital because no system is completely immune. Early warning allows you to respond before attackers cause significant damage.

Traffic monitoring helps identify suspicious patterns. For instance, a sudden spike in login attempts from different locations or devices indicates credential testing.

Implementing rate limiting reduces the number of allowed login attempts per IP address. Web application firewalls can block traffic that matches automated bot behaviour.

Behavioural analytics tools provide deeper visibility. They learn normal user behaviour and detect deviations such as repeated failed logins or rapid session creation.

Retailers should establish automated alerts for unusual login activity. Integration with a Security Information and Event Management (SIEM) system improves response coordination.

Regular security audits confirm that detection tools remain effective. Attackers continuously adjust their methods, so defences must evolve too.

Cybergen recommends using managed detection and response services to maintain constant monitoring. These services combine automation with expert analysis to identify attacks in progress.

Reducing the Impact of Breaches

Even with strong defences, incidents still occur. Preparedness determines how much damage follows.

Incident response planning ensures that everyone knows their role during an attack. Teams must act quickly to contain compromised accounts, block malicious IPs, and notify affected users.

Data backup and recovery procedures reduce downtime. Backups must be encrypted and tested regularly to confirm they restore correctly.

Customer communication plays a critical role. Clear, honest updates help maintain trust during recovery. Delayed or vague communication worsens reputational damage.

Retailers should also coordinate with payment providers and law enforcement when fraud occurs. Sharing intelligence helps prevent future attacks.

Continuous improvement is essential. Every incident provides insights to strengthen future defences. Conduct post-incident reviews to identify what worked and what failed.

Building a Security Culture

Technology alone will not stop credential stuffing. Human behaviour remains the deciding factor.

Staff training is the foundation of good cybersecurity. Employees should understand how credential stuffing works and how to recognise suspicious account activity.

Retailers should foster a culture where security is everyone’s responsibility. Regular workshops, clear policies, and leadership involvement help reinforce this mindset.

Encourage collaboration between IT, marketing, and customer service teams. These departments often identify different signs of attack. For example, customer complaints about unauthorised purchases can alert IT to an active breach.

Cybergen advises conducting regular simulated attack exercises to test readiness. These exercises build confidence and prepare teams to respond quickly.

Investing in human awareness delivers long-term value. When your people understand security risks, your technology becomes more effective.

The Role of Cybergen

Cybergen supports retail businesses with end-to-end cybersecurity services. From vulnerability assessments to managed detection, Cybergen provides expertise tailored to retail operations.

Through its training programmes and consulting services, Cybergen helps organisations strengthen authentication systems, detect bot activity, and recover from breaches.

The company’s managed security services include real-time monitoring, incident response, and strategic advisory support. These solutions align with recognised frameworks such as Cyber Essentials and NIST.

Cybergen’s goal is to build confidence through knowledge and preparation. By working together, retailers can protect their customers, maintain compliance, and reduce operational risk.

Summary

Credential stuffing has become one of the most common and costly threats facing retailers. Attackers exploit password reuse and automation to compromise accounts at scale. The consequences affect finance, reputation, and compliance.

Prevention depends on strong authentication, continuous monitoring, and human awareness. Retailers who invest in these measures protect both their business and their customers.

Cybergen offers expert guidance and managed services to strengthen your defences and ensure your systems remain secure. The time to act is now. Security builds trust, and trust drives growth.

References

Verizon (2024) Data Breach Investigations Report 2024. Verizon Business.

British Retail Consortium (2023) Retail Crime and Cyber Threats Report. BRC.

National Cyber Security Centre (2024) Cyber Essentials Technical Controls. NCSC.

National Institute of Standards and Technology (2023) Cybersecurity Framework Version 1.1. NIST.  

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