Companies must pay close attention to the most common control failures, or it will become incredibly challenging to maintain Payment Card Industry Data Security Standard (PCI DSS) compliance.

Failure to maintain compliance is not just an audit issue; it can lead to devastating fines, imposed business restrictions, and the ultimate rejection of your credit card processing facilities. Unfortunately, many companies have not had sufficient time or resources to properly pressure-test their security controls against all PCI DSS requirements.

Based on global experience implementing and auditing PCI DSS environments, these are the five most common control failures that organizations struggle to achieve—and exactly how to fix them.

1. Requirement 1.1.3.a: Failure to Establish a Data Flow Diagram

The Failure: It is of utmost importance for businesses dealing with cardholder data to know exactly where that data resides. However, most businesses fail this requirement because payment card data remains unmanaged, uncategorized, and dispersed across multiple enterprise databases.

As an industry analyst noted following the high-profile Target data breach (which exposed 40 million credit and debit cards): "This is a breach that should’ve never happened. The fact that three-digit CVV security codes were compromised shows they were being stored." Storing sensitive authentication data was banned by the PCI SSC, but because Target lacked visibility into their data flows, the vulnerability remained undiscovered.

The Fix: To meet this control, businesses must meticulously map the systems through which cardholder data enters, traverses, and leaves the organization. Utilizing an automated data discovery and classification tool allows organizations to hunt for hidden shadow data, securely label transport mechanisms, and build an accurate, audit-ready diagram of the Cardholder Data Environment (CDE).

2. Requirement 12.1: Failure to Maintain a Security Policy

The Failure: The requirement is straightforward: "Establish, publish, maintain, and disseminate a security policy." Yet, while many businesses have established security policies on paper, they fail to maintain them, opening multiple vulnerabilities in the payment lifecycle. Companies often document and publish a policy merely to pass an audit, but fail to actually integrate it into their daily operations.

The Fix: When creating a security policy, the organizational design must be actively engaged. First, ensure the policy directly addresses every requirement of PCI DSS, structuring it to match the exact order and language of the sub-requirements. Furthermore, businesses must review, test, and update these policies at least annually (or whenever the environment changes) to effectively maintain security.

3. Requirement 12.3.3: Failure to List Devices and Personnel

The Failure: Tracking card data is directly proportional to tracking the people and devices that process and store it. Most businesses attempting to comply fail this critical control simply because they do not track their endpoint devices and user permissions accurately as their workforce scales.

The Fix: The assurance and operations members of risk and compliance teams must actively update device lists alongside employee off-boarding and on-boarding processes. The best solution is to maintain a continuously updated, accurate inventory featuring proper labeling. Leverage structured managed compliance programs to establish a strict frequency for updating this list across four critical columns: Device, Employee, Data Type, and Access Type.

4. Requirement 12.10.1.a: Failure to Verify Incident Response Plans

The Failure: Off-the-shelf security incident response plans remain outdated and entirely ineffective against today's ever-changing threat landscape. During global incident response exercises, assessors frequently observe response failures stemming from severe organizational shortcomings—namely, a lack of coordination, slow business recovery, and poor data backup analysis. Failing to plan means planning to fail.

The Fix: Businesses must actively verify their incident response plans by simulating a real-world attack every six months to assess how key stakeholders respond under pressure. In the case of a suspected or confirmed security breach, merchants must act within 24 hours to alert all necessary parties. Partnering with elite Digital Forensics and Incident Response (DFIR) teams ensures your internal staff is trained to isolate threats, document lessons learned, and meet strict legal reporting requirements without hesitation.

5. Requirement 12.5.5: Failure to Monitor and Control Data Access

The Failure: All data custodians who grant access to sensitive data (based on a strict business "need-to-know") must be responsible for monitoring access hygiene. However, businesses frequently ignore the importance of bestowing this responsibility on a specific individual with formal accountability. This failure has become critical with the rise of remote working, as companies struggle to ensure technical safeguards are actively enforcing access limits.

The Fix: A dedicated data security specialist—with a straight-line reporting structure to executive authority (CIO, CISO, or Risk Manager)—must be formally nominated for these responsibilities. Assessors highly recommend that these professionals implement rigorous Privileged Access Management (PAM) controls and update data access charts on a strict monthly basis.

Conclusion

Although the regulatory landscape for PCI SSC requirements continues to evolve, the foundation of a successful compliance program remains the same: encouraging businesses to secure cardholder data by embracing a true culture of compliance.

Risk and compliance teams must remain focused on how to enhance their controls continuously, rather than treating audits as an annual checklist. By proactively addressing the five critical control failures outlined above, organizations can drastically reduce their risk exposure and build a resilient, audit-ready payment environment.

Frequently Asked Questions (FAQs)

What is the most common reason companies fail their PCI DSS audit?

‍One of the most frequent reasons for failure is a lack of accurate scoping (Requirement 1.1.3.a). If an organization does not have an accurate data flow diagram, they often inadvertently leave critical systems unprotected or store sensitive cardholder data in hidden, unmonitored locations.

How often should a PCI DSS security policy be updated?

‍Requirement 12.1 mandates that information security policies must be reviewed at least annually, and updated immediately whenever there is a significant change to the business environment or network architecture.

Why do incident response plans fail during an actual breach?

‍Incident response plans typically fail because they are treated as static documents rather than operational playbooks. If the plan is not tested through simulated real-world attacks (tabletop exercises) every six months, stakeholders will lack the coordination and speed necessary to contain a live breach within the mandated 24-hour window.

What is the principle of "need-to-know" in PCI DSS?

‍The "need-to-know" principle (tied to Requirement 12.5.5 and Requirement 7) ensures that employees are granted access only to the specific cardholder data and systems absolutely necessary to perform their job functions. All other access must be strictly denied by default.

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