PCI DSS v4.0 · PCI SSC

PCI DSS v4.0. Scoped, segmented, attested.

Self-Assessment Questionnaires for smaller merchants. Reports on Compliance via QSA partner for Level 1. Tokenization, segmentation, and the v4.0 requirements that go enforceable in 2025.

What it is·PCI Security Standards Council (PCI SSC)

Payment Card Industry Data Security Standard governing storage, processing, and transmission of cardholder data.

PCI DSS is the security standard for any organization that stores, processes, or transmits cardholder data. The current version is v4.0, released March 2022, with enforcement dates phased through 2025. Compliance level depends on transaction volume: Levels 2, 3, and 4 attest via Self-Assessment Questionnaire (SAQ); Level 1 (over six million transactions per year for most card brands) requires an annual Report on Compliance (ROC) signed by a Qualified Security Assessor (QSA).

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Who needs it

Any merchant accepting cards or any service provider in the cardholder data flow. SaaS that processes payments via Stripe, Adyen, or similar processors typically reduces scope through tokenization and SAQ A or SAQ A-EP. Companies with on-premise card data or unusual flows face larger SAQ D scope or Level 1 ROC requirements.

§02

The HSD playbook for PCI DSS

HSD begins with cardholder data flow mapping and scope determination. For most SaaS, the goal is reducing scope to SAQ A or SAQ A-EP through tokenization. We harden the cardholder data environment if there is one, implement segmentation, run quarterly ASV scans through an Approved Scanning Vendor partner, conduct annual penetration tests, and produce the SAQ. For Level 1 customers, we coordinate with a QSA partner who issues the ROC and the AOC.

§03

Timeline

Weeks 1 to 2

Scoping and CDE definition

Cardholder data flow diagrams, scope determination, segmentation review

Weeks 2 to 6

Control implementation

v4.0 requirements: targeted risk analysis, multi-factor for all access into the CDE, network security controls, secure software development

Weeks 4 onward

ASV scans

Quarterly external scans by Approved Scanning Vendor partner; remediate failed checks

Weeks 6 to 8

Penetration test

Annual external and internal penetration test against the CDE and segmentation controls

Weeks 8 to 10

SAQ or ROC

SAQ A through D for self-assessment, or QSA fieldwork and Report on Compliance for Level 1

After report

Attestation and ongoing

AOC submission, continuous monitoring of in-scope controls

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Cost reality

Line itemRangeNote
Software platforms covering PCI DSSUSD 10,000 to 30,000 per yearPCI DSS support varies; deeper than SOC 2-only platforms
Remediation and SAQ preparationUSD 20,000 to 60,000Lower for SAQ A through tokenization; higher for SAQ D or on-premise CDE
Approved Scanning Vendor (quarterly)USD 1,000 to 5,000 per yearRequired regardless of merchant level
QSA fieldwork (Level 1 ROC)USD 30,000 to 80,000Significant variability based on CDE complexity and geographic scope
HSD bundled programScoped per programEngineers, ASV partner, QSA partner coordination in one engagement
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What auditors check

Cardholder data flow diagram

Auditor wants to see exactly where card data enters, traverses, and leaves the environment. Wrong or stale diagram is a frequent finding.

Segmentation that actually segments

If segmentation is claimed to reduce scope, the auditor tests that the segmentation controls function as documented.

Multi-factor for all access into the CDE

v4.0 made MFA mandatory for all access into the CDE, not only administrative. Enforceable from March 31, 2025.

Quarterly ASV scans, all passing

Failed scans have to be remediated and rescanned until passing within ninety days of the failure.

Annual external and internal penetration tests

Required by Requirement 11.4. Reports must be retained and findings remediated; segmentation testing is separate.

Targeted risk analysis (v4.0 new)

Customized approach in v4.0 requires per-control targeted risk analysis. Generic risk assessments do not satisfy the requirement.

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Common pitfalls

Wrong SAQ

Choosing SAQ A when SAQ A-EP applies (or D when A applies) creates either gaps or unnecessary work. Scope determination is the first thing to get right.

Segmentation claimed but not enforced

Logical segmentation that does not actually prevent traffic between zones fails segmentation testing.

Missing v4.0 enforcement dates

Several v4.0 requirements became enforceable in March 2025. Operating against v3.2.1 controls without v4.0 readiness is a finding.

Stale cardholder data flow

Flow diagrams not updated after architecture changes. Real flows diverge from documented flows; auditors notice.

Penetration test scope errors

Penetration test scoped to the wrong assets, or conducted by an unqualified tester, leads to ROC delays and rework.

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FAQ

What changed in PCI DSS v4.0?+
Customized approach option, targeted risk analyses, expanded MFA requirements, stronger authentication, and a phased compliance schedule with most new requirements enforceable from March 31, 2025.
Do I need a QSA?+
Only if you are Level 1 (over six million transactions per year) or if your acquirer or card brand requires it. Most SaaS handle PCI through SAQ self-assessment.
Can tokenization reduce scope?+
Yes. Tokenization is the standard scope-reduction strategy: cardholder data lives at the processor, your environment handles tokens. Most SaaS using Stripe or similar achieve SAQ A or SAQ A-EP.
Does HSD perform the QSA work?+
No. We coordinate accredited QSA partners. The Report on Compliance and Attestation of Compliance must be issued by an independent QSA.
What is the difference between an SAQ and a ROC?+
SAQ is self-attestation by the merchant; ROC is a fieldwork-based report by a QSA. Level 1 merchants require ROC; smaller merchants typically use SAQ.
How often is PCI DSS validated?+
Annually. The AOC has a date and a one-year validity window in practice; quarterly ASV scans and annual penetration tests run continuously through the validity period.

Want PCI DSS scoped for your stack?

Thirty-minute call. Fixed-scope quote inside a week. We tell you honestly when PCI DSS should wait or when it should lead.