By Kate Howe June 5, 2025
Maintaining compliance with the Payment Card Industry Data Security Standard is essential for businesses that accept credit or debit card payments. PCI DSS was designed to ensure that cardholder data is stored, processed, and transmitted securely. While many businesses work hard to meet these requirements, common mistakes can lead to non-compliance. These oversights can result in data breaches, financial penalties, and loss of customer trust.
Understanding what causes non-compliance is the first step toward building a secure payment environment.
Lack of Understanding of PCI DSS Requirements
One of the most frequent issues that lead to non-compliance is a basic lack of understanding of what PCI DSS entails. The standard includes twelve core requirements that cover everything from network security to access control and data protection.
Overlooking Scope
Many businesses incorrectly define the scope of their cardholder data environment. Failing to include all systems that interact with or impact cardholder data results in incomplete compliance measures. It is important to conduct a proper scoping exercise before beginning any PCI initiative.
Assuming Compliance is a One-Time Task
Some organizations mistakenly treat compliance as a project with a start and end date. In reality, PCI DSS requires continuous monitoring and maintenance. Threats evolve, systems change, and new vulnerabilities arise, all of which require ongoing attention.
Inadequate Network Security
Another major area where businesses fall short is network security. PCI DSS requires secure firewall configurations and monitoring systems to detect unauthorized access.
Default Passwords and Configurations
Using default settings for network devices, software, and hardware is a common mistake. These default configurations are well known and easily exploitable. All devices should be updated with unique, strong passwords and properly configured security settings.
Unsegmented Networks
Failing to segment networks properly increases the risk of data breaches. Cardholder data should be isolated from other parts of the network to limit exposure in case of an incident. Network segmentation also reduces the scope of PCI DSS, making compliance easier and more cost-effective.
Poor Data Management Practices
PCI DSS places a strong emphasis on how cardholder data is stored and accessed. Unfortunately, businesses often fail to follow secure data management protocols.
Storing Sensitive Authentication Data
PCI DSS prohibits storing certain types of sensitive authentication data after authorization. This includes full magnetic stripe data, card validation codes, and PINs. Some businesses, however, keep this data longer than necessary, exposing themselves to high levels of risk.
Lack of Data Encryption
Cardholder data should be encrypted both at rest and in transit. Failing to use strong encryption methods makes it easier for cybercriminals to intercept and exploit the data. Businesses should ensure encryption keys are securely stored and managed.
Weak Access Control
Access to systems and data should be restricted to only those who need it for their job roles. This principle of least privilege is central to PCI DSS, but many businesses ignore it.
Shared User Accounts
Using shared logins for multiple employees makes it difficult to track user activity and increases the risk of unauthorized access. Each user should have a unique ID, and access rights should be reviewed regularly.
No Multi-Factor Authentication
Single-factor authentication is no longer sufficient for securing access to systems containing sensitive information. PCI DSS now requires multi-factor authentication for all administrative access, but not all businesses have implemented this.
Inconsistent Monitoring and Logging
PCI DSS requires businesses to track and monitor all access to network resources and cardholder data. Logs must be retained and reviewed regularly to detect suspicious activity.
Failing to Monitor Logs
Having a logging system in place is not enough. Logs must be actively monitored to identify anomalies or unauthorized access. Many businesses collect logs but do not review them, rendering the effort ineffective.
Inadequate Log Retention
PCI DSS requires logs to be retained for at least one year, with the most recent three months available for immediate analysis. Some businesses fail to store logs properly or delete them too soon, which can hinder investigations after a security incident.
Irregular Vulnerability Management
Ongoing vulnerability management is a critical part of maintaining PCI DSS compliance. This includes regularly updating software, scanning systems, and patching identified weaknesses.
Skipping Regular Scans
Businesses must perform both internal and external vulnerability scans at least quarterly and after any major changes. Skipping these scans leaves systems open to known threats.
Ignoring Security Patches
Delaying or ignoring software updates and patches is a common mistake. Hackers often target known vulnerabilities, and unpatched systems present an easy opportunity. Businesses must implement a process for timely patch management.
Failure to Test Security Systems
PCI DSS requires regular testing of security systems and processes. This ensures that controls are functioning as expected and are capable of protecting cardholder data.
No Penetration Testing
Penetration testing simulates real-world attacks to identify weaknesses. Many businesses skip this step or perform it infrequently, missing critical vulnerabilities that could be exploited.
Lack of Intrusion Detection
Intrusion detection systems help identify and alert to potential breaches. Without them, businesses may not be aware that an attack is taking place. PCI DSS requires the use of these systems for proper security monitoring.
Incomplete Security Policies
Security policies serve as the foundation of a business’s compliance efforts. PCI DSS requires written policies that are regularly reviewed and updated.
Outdated or Missing Documentation
Policies that are outdated or incomplete create gaps in compliance. All security policies should reflect current operations and include procedures for training, access control, data retention, and incident response.
Lack of Employee Training
Employees play a significant role in maintaining security. Without proper training, they may unknowingly compromise compliance. Training should be part of the onboarding process and refreshed regularly.
Neglecting Third-Party Risks
Many businesses rely on third-party vendors for payment processing, cloud storage, or other services. These vendors can introduce compliance risks if not properly managed.
Not Reviewing Vendor Compliance
Businesses are responsible for ensuring that third-party providers also comply with PCI DSS. This includes reviewing their compliance status and contractual obligations.
No Incident Response Coordination
If a third-party vendor experiences a breach, businesses must have a coordinated response plan. Without one, delays and confusion can worsen the impact of the incident.
Conclusion
Achieving PCI DSS compliance is not an easy task, but it is essential for protecting customer data and maintaining trust. The most common mistakes are often preventable with the right awareness and planning. By understanding where businesses typically go wrong, you can take proactive steps to stay compliant.
From maintaining strong network security to managing vendor relationships, every part of the payment environment must be reviewed and protected. Compliance is not just a requirement. It is a commitment to your customers and your brand’s long-term success.