Skip to content

PCI CDE Penetration Testing Services

PCI DSS Penetration Testing for Your Cardholder Data Environment

If your payment environment has a weakness, attackers might reach systems that handle cardholder data. PCI CDE penetration testing helps your business find these vulnerabilities, check your IT security controls, and see if attackers could break into your payment systems.

Tanner Security provides PCI DSS penetration testing for Cardholder Data Environments (CDEs), including internal and external network penetration testing, segmentation testing, application-layer testing, vulnerability validation, and remediation verification.

Our team of consultants use automated tools and manual testing to give you a clear view of your payment environment. We do more than just find vulnerabilities. We show how attackers could use them and explain what your team should do next.

PCI DSS v4.0.1 requires applicable internal and external penetration testing as part of its security requirements. Requirement 11.4.2 addresses internal penetration testing, while Requirement 11.4.3 addresses external penetration testing. Under the Defined Approach, testing is performed at least every 12 months and after significant IT or application changes. The requirements also address tester qualifications and independence.

Schedule a PCI Penetration Testing Consultation

Contact Tanner Security to discuss your CDE, PCI requirements, testing, and gap assessments.

PCI CDE Penetration Testing Services

What Is PCI CDE Penetration Testing?

PCI CDE penetration testing is an authorized security assessment that simulates attack techniques against systems and networks within or connected to a company’s Cardholder Data Environment.

The goal is not just to find vulnerabilities. A penetration test checks if those weaknesses could let someone gain unauthorized access, move through your systems, or compromise payment card data.

PCI DSS Requirement 11.4.1 calls for a documented penetration-testing methodology that uses industry-accepted approaches and addresses the CDE perimeter and critical systems. The method should consider testing from inside and outside the network, segmentation controls, application-layer security, network-layer security, and relevant threats and vulnerabilities.

A good PCI penetration test looks at your payment environment from an attacker’s point of view.

What Is the Cardholder Data Environment?

The Cardholder Data Environment, commonly called the CDE, includes systems and components that store, process, or transmit payment card account data, as well as other components that can affect the security of those systems.

Defining the CDE correctly is one of the most important steps in a PCI assessment. Your PCI scope depends on how payment data moves through your environment and which systems can affect its security.

A CDE may include payment-processing systems, databases, servers, firewalls, POS systems, e-commerce infrastructure, payment applications, authentication systems, and connections to third-party payment providers.

The exact scope is different for every business.

Tanner Security begins each project by learning about your payment setup and identifying the systems, connections, and security controls that are important for the test.

Why PCI DSS Requires Penetration Testing

PCI DSS penetration testing is different from a vulnerability assessment or a compliance questionnaire.

A scanner finds known vulnerabilities, old software, and configuration issues. A penetration test goes further by trying to exploit those weaknesses and see what real impact they could have.

Attackers rarely rely on one vulnerability in isolation. An attacker might discover an exposed service, exploit a weak configuration, obtain credentials, escalate privileges, move laterally, and eventually reach a system that processes payments.

A good penetration test finds these attack paths before an actual attacker does.

For your leadership team, the key question is not just if a vulnerability exists, but whether an attacker could use it to reach important systems.

We love working with the Information Security team at Tanner Security Consultants. They customized their PCI penetration testing service offerings to fit our needs and put together a team of well-qualified individuals to work with us. Their team has exceeded my expectations.

Brad B. – President

PCI DSS Penetration Testing Requirements

PCI DSS v4.0.1 separates internal and external penetration-testing requirements.

Internal PCI Penetration Testing: Requirement 11.4.2 addresses internal penetration testing. Under the Defined Approach, testing is conducted at least once every 12 months and after significant IT or application upgrades or changes. Testing must be conducted by a qualified internal resource or a qualified external third party, and the tester must maintain independence.

Internal testing helps determine what an attacker could accomplish after gaining some level of access to an internal or trusted network.

Tanner Security can evaluate internal network security, authentication controls, opportunities for privilege escalation, lateral movement, segmentation, Active Directory, and systems that connect to or support the CDE.

External PCI Penetration Testing: Requirement 11.4.3 addresses external penetration testing. Under the Defined Approach, testing is conducted at least every 12 months and after significant IT or application upgrades or changes.

External testing examines the attack surface an attacker can reach from outside the environment. Depending on scope, this can include public IP addresses, firewalls, VPN gateways, remote-access services, internet-facing applications, APIs, and publicly accessible cloud infrastructure.

Internal and external testing answer different questions. This is why a full PCI testing program usually needs both types.

PCI Segmentation Testing

PCI Segmentation Testing

Network segmentation can reduce PCI scope by isolating systems that handle cardholder data from other parts of the environment.

Segmentation reduces risk if it works as intended.

PCI DSS Requirement 11.4.5 addresses penetration testing of segmentation controls when a company relies on segmentation to isolate the CDE. Under the Defined Approach, testing is performed at least every 12 months and after changes to segmentation controls or methods.

Tanner Security tests segmentation by approaching it from an attacker’s perspective, not just by reviewing network diagrams or firewall rules.

The question is simple:

“Can an attacker move from an out-of-scope network into the Cardholder Data Environment?”

The answer to this question can affect both your security and your PCI scope.

Application-Layer PCI Penetration Testing

Payment applications can create risks that network testing alone might miss.

PCI DSS Requirement 11.4.1 specifically includes application-layer penetration testing as part of the penetration-testing methodology.

Tanner Security can evaluate authentication, authorization, session management, input validation, business logic, API security, access controls, sensitive information exposure, administrative functionality, and other application security risks when these components fall within the engagement scope.

This is especially important for businesses with custom payment applications, e-commerce platforms, customer portals, or APIs that connect to payment systems.

Need Web Application PCI Pen Test?

Get a penetration test of your internal, external, application, and segmentation security controls.

Our PCI CDE Penetration Testing Methodology

We start every project by defining authorization, objectives, rules of engagement, and scope.

  1. Scope and Planning: We work with your team to understand the CDE, critical systems, network architecture, payment-processing workflows, third-party connections, and testing requirements. We identify key systems and create a testing plan that minimizes unnecessary operational risk.
  1. Reconnaissance: Our consultants examine the approved environment to find potential attack paths, exposed services, technologies, applications, trust relationships, and other relevant information. For external testing, we start from the attacker’s perspective. For internal testing, we examine what an attacker could discover and exploit after gaining internal access.
  1. Automated Security Testing: We use security testing tools to find vulnerabilities, exposed services, configuration weaknesses, and other potential entry points. Automated testing covers many areas, but it cannot replace manual analysis.
  1. Manual Validation and Exploitation: We manually validate important findings and attempt controlled exploitation where appropriate. This helps us see whether a vulnerability could be used to compromise your systems or allow an attacker to move further into your environment.
  1. Privilege Escalation and Lateral Movement: Where the scope permits, we examine what an attacker could accomplish after gaining an initial foothold. The assessment can include privilege escalation, credential abuse, lateral movement, segmentation testing, and attempts to reach systems that support the CDE.
  1. Reporting and Remediation: Our report explains what we tested, what we found, why it matters, and how your team can address the issues. We focus on findings based on risk, not just by listing technical issues. After you fix the problems, Tanner Security can retest to make sure the vulnerabilities are gone.

Who Needs PCI CDE Penetration Testing?

PCI penetration testing can apply to retailers, e-commerce companies, financial services firms, healthcare businesses, hospitality companies, software providers, professional services firms, and other businesses that operate payment environments.

The complexity of your environment often matters more than your company’s size.

A small business with a simple hosted payment setup will have a very different testing scope than a large company running its own payment applications, databases, networks, and integrations.

Tanner Security can help you determine the right testing scope before starting the project.

Why Choose Tanner Security for PCI Penetration Testing?

Tanner Security is an independent cybersecurity consulting firm. We do not sell security products or subscriptions, so our recommendations focus on your security needs, not on selling products.

Our team has over 20 years of experience in cybersecurity consulting, including penetration testing, network security, web application testing, cloud security, IT risk assessments, and compliance.

We use proven methods and hands-on technical analysis. Your assessment is more than just an automated report. Our consultants look for attack paths, review findings, assess business impact, and give practical advice on fixing issues.

A Tanner Security PCI penetration test should answer three main questions:

  1. What could an attacker exploit?
  2. How far could an attacker get?
  3. What should your company fix first?

Talk With a PCI Penetration Testing Expert

Talk with us about your CDE, testing needs, past findings, or any upcoming PCI assessments.

PCI DSS Compliance Consulting Services

Tanner Security approaches PCI compliance as a security and risk management issue, not just a paperwork task.

PCI Gap Assessments: A PCI gap assessment compares your current security controls and practices against the PCI DSS requirements that apply to your environment. We find gaps, explain why they matter, help you set priorities, and work with your team to create a practical plan that addresses the most serious issues first. A gap assessment is especially helpful if your company is preparing for its first PCI assessment, moving to PCI DSS v4.0.1, changing payment platforms, expanding its payment environment, or responding to past assessment findings.

PCI DSS Compliance Assessments: A PCI compliance assessment provides a wider review of your security controls against applicable PCI DSS requirements. Tanner Security evaluates areas such as access control, authentication, vulnerability management, network security, security policies, logging, monitoring, incident response, and security testing. The goal goes beyond simply answering “yes” or “no.” We want your leadership team to understand where risks exist, why the controls matter, and what your company should do next.

PCI Policy Consulting: PCI DSS requires more than technical controls. Your company also needs policies and procedures that support the security of payment card data. Tanner Security can review and develop policies covering information security, acceptable use, access management, vulnerability management, incident response, third-party risk, security awareness, data retention, and other areas relevant to your PCI program. We focus on practical policies your employees can use, not just generic documents that get ignored.

PCI CDE Penetration Testing: Penetration testing goes beyond identifying possible vulnerabilities. It attempts to determine whether an attacker can exploit weaknesses and what access that attacker could obtain. Tanner Security performs PCI CDE penetration testing to evaluate the security of systems and networks that support payment card processing. Our testing can include vulnerability identification, manual validation, exploitation, privilege escalation, lateral movement, and other techniques that fit the approved scope.

PCI CDE Penetration Testing FAQ’s

A PCI CDE penetration test evaluates the security of IT systems and networks that store, process, or transmit payment card data, as well as other components that affect CDE security. The assessment uses attack methods to identify and validate exploitable weaknesses. We have found that mobile app pen testing is often overlooked for PCI compliance.

Yes. Applicable PCI DSS requirements include internal and external penetration testing. Under the Defined Approach, Requirements 11.4.2 and 11.4.3 call for applicable internal and external testing at least every 12 months and after significant IT or application changes. Read more about why PCI penetration testing is important for your business.

Applicable internal and external penetration tests must occur at least once every 12 months under the Defined Approach, with additional testing after upgrades or other changes. Read more about how often your company should conduct penetration tests.

The penetration testing scope should cover the applicable CDE perimeter and critical systems identified through the company’s PCI methodology and assessment requirements. Proper scoping matters because a test that omits an important system can provide an incomplete picture of risk. Read more about when a company can say they are PCI compliant.

When a company uses segmentation to isolate the CDE from other networks, PCI DSS includes specific segmentation-testing requirements. Requirement 11.4.5 addresses testing segmentation controls at least every 12 months and after changes to those controls or methods under the Defined Approach. Contact Tanner Security if you are needing PCI DSS Consulting.

No. Network vulnerability assessments identifies known weaknesses, while penetration testing assesses whether those weaknesses can lead to a meaningful compromise. PCI DSS treats these as different security activities.

PCI DSS permits qualified internal resources or qualified external third parties to perform applicable penetration testing, subject to the requirements around qualifications and organizational independence. Your payment brand, acquiring bank, assessor, or other compliance requirements may also affect the validation process.

PCI DSS allows qualified internal resources to perform applicable penetration testing when the requirements, including independence, are satisfied. Many companies choose an external provider to obtain an independent assessment. Read more about some tips and tricks to becoming PCI compliant.

The process must address the CDE perimeter and critical systems and consider internal and external testing; application- and network-layer testing; segmentation, where applicable; relevant threats and vulnerabilities; and documented processes for risk assessment and remediation.

It can. PCI DSS Requirement 11.4.1 specifically includes application-layer penetration testing as part of the penetration-testing methodology. Tanner Security can test web applications and APIs when they fall within the engagement scope.

The timeline depends on the size and complexity of the CDE, the number of external and internal assets and applications, the segmentation architecture, the testing objectives, and the rules of engagement. Tanner Security defines the scope before testing, so the engagement reflects the actual environment.

Penetration testing costs depends primarily on scope. A small environment with a limited external attack surface may require substantially less testing than a large CDE with extensive internal systems, applications, segmentation, and payment-processing components. Tanner Security provides fixed-fee proposals based on the defined testing scope.

PCI DSS v4.0.1 provides corrections and clarifications to PCI DSS v4.0. PCI SSC released v4.0.1 in June 2024, and v4.0 retired on December 31, 2024.

Tanner Security can help define the testing scope, perform internal and external penetration testing, evaluate segmentation controls, test applications and APIs, validate vulnerabilities, provide remediation recommendations, and perform retesting after your team addresses findings.

Protect Your Payment Environment Before an Attacker Tests It

PCI compliance should mean more than simply meeting a requirement.

A penetration test gives your business a clear view of what an attacker could exploit, how far they could go, and where your security controls need improvement.

Tanner Security uses PCI expertise, penetration testing skills, and broad cybersecurity experience to help businesses find weaknesses and strengthen the systems that protect payment card data.

Related Insights

View All