PCI DSS in the cloud requires you to define scope precisely. Map every system, network path, and third-party service that stores, processes, or transmits cardholder data before designing controls. Scope creep is expensive—every in-scope system multiplies your compliance burden.
Use network segmentation to isolate the cardholder data environment (CDE) from the rest of your infrastructure. In cloud terms this typically means dedicated accounts or VPCs, strict security groups, and no unnecessary connectivity between CDE and non-CDE workloads.
Encryption is non-negotiable: data at rest and in transit must use strong cryptography, with keys managed separately from the data they protect. Document key rotation procedures and access restrictions. Cloud KMS services help, but you must still document who can access keys and how key usage is logged.
Access control must enforce least privilege with MFA for all administrative access to in-scope systems. Quarterly access reviews and automated deprovisioning reduce standing privilege risk. PCI DSS v4.0 places increased emphasis on access control testing and defined security roles.
Logging and monitoring need to cover authentication events, privileged actions, and changes to security configurations. Retain logs for the period required by PCI DSS and test alerting regularly. Centralise logs outside the CDE so they remain available even if the CDE is compromised.
Vulnerability management must include external and internal scanning, patch SLAs based on risk, and documented exceptions with compensating controls. Cloud workloads change frequently—tie scanning to deployment pipelines so new resources are assessed automatically.
Secure software development practices apply to any custom code touching cardholder data. Code review, dependency scanning, and separation of development and production environments should be documented and evidenced.
Third-party service providers—including your cloud provider—must be managed under PCI DSS requirements. Maintain responsibility matrices, review Attestations of Compliance (AOCs), and document which controls you implement versus which the provider manages.
Before go-live, run a pre-audit gap assessment against PCI DSS v4.0 requirements. Fixing scope ambiguity and evidence gaps early is far cheaper than discovering them during a formal assessment. Engage a Qualified Security Assessor (QSA) early for complex environments.
After go-live, treat compliance as continuous. Quarterly scans, annual assessments, and change management for any CDE modification are ongoing obligations—not one-time project milestones.