Skip to content
Audit-Checklist

Cloud ISO · ISO Standards

ISO/IEC 27017: cloud control guidance that actually names who does what

How CSPs and cloud customers use ISO 27017 — shared responsibility, virtualization, and how it extends ISO 27001 for cloud services.

6 min read

ISO/IEC 27017 provides cloud-specific security control guidance that extends ISO 27001 and ISO 27002. Its practical value is clarity: cloud providers and cloud customers need to know which party configures, monitors, hardens, logs, responds, and proves each control.

The checklist helps execute a 27017 program, but the guide frames the judgment. Shared responsibility is not a slogan; it is a set of operational decisions about tenant IAM, virtual networks, administrative access, encryption keys, monitoring, backup, and support boundaries.

In 2026, buyers ask for 27017 because cloud risk is no longer abstract. Multi-cloud, managed Kubernetes, SaaS platforms, customer-managed keys, and automated deployment pipelines make a generic ISO 27001 statement feel incomplete unless cloud responsibilities are explicit. For ISO 27017, the guide should turn shared responsibility into engineering evidence. A useful matrix names not only provider and customer but the exact team, control plane, configuration, log source, review cadence, and escalation route. Tenant IAM is a good test: the CSP may secure identity services, while the customer chooses administrators, roles, MFA enforcement, service accounts, and emergency access. Key management is another test because the phrase customer-managed can hide several operating models. The checklist should help teams compare architecture, contract language, support procedures, and customer-facing claims. If those do not agree, the cloud security story will fail under procurement or audit questioning. A useful way to read the rest of this guide is to separate evidence from judgment. Evidence shows that an activity happened: a review, record, test, approval, training, scan, exercise, assessment, or decision. Judgment explains why the activity was scoped that way, why the risk treatment is proportionate, why an exception is acceptable, and what would cause the decision to change. The paired checklist should collect evidence and owners, while the guide should help teams avoid false certainty. For each topic, ask what a knowledgeable reviewer would challenge after seeing the first answer. They may ask whether the scope matches production, whether suppliers are included, whether recurring work is current, whether leadership approved trade-offs, and whether public or customer-facing claims match operations. That second layer is where preparation becomes credible. It also keeps teams from overclaiming, because a documented limitation with a plan is usually stronger than a broad statement no one can support. Keep a dated rationale beside the evidence so reviewers can see what changed, who approved the interpretation, and which operating signal would trigger a fresh review. Keep the reviewer-facing story specific enough that another team can repeat the analysis without guessing.

What ISO 27017 actually is

ISO 27017 is a code of practice for information security controls for cloud services. It is usually used with ISO 27001 certification, either by cloud service providers, cloud customers, or SaaS companies that operate on top of infrastructure providers.

The standard highlights cloud-specific concerns such as shared roles, virtualization, administrator operations, segregation, monitoring, customer asset handling, and cloud service configuration. It helps convert broad controls into cloud operating procedures.

Provider and customer perspectives differ. A CSP may need evidence for service architecture, isolation, privileged operations, and customer communication. A customer or SaaS operator may need evidence for tenant configuration, IAM, logging, encryption, backups, and incident handling.

Decisions the checklist will not make for you

The checklist cannot decide which controls are inherited and which are tenant responsibilities. Teams must read provider documentation, contracts, assurance reports, architecture, and actual configuration to produce a shared responsibility matrix that people can use.

It also cannot determine key-management promises. If sales says customer-managed keys, engineering must define whether customers control keys, whether the provider can access plaintext, how rotation works, and what happens during support or recovery.

The checklist cannot design break-glass access. Organizations need to decide who can use emergency access, how it is approved, how it is logged, how credentials are protected, and how access is reviewed after use.

Where cloud programs actually fail

Teams often assume the cloud provider covers tenant IAM. In reality, the provider secures underlying services while the customer controls users, roles, MFA, service accounts, keys, and privilege design. Misconfigured IAM is still a customer problem.

Break-glass accounts are frequently missing or unmanaged. A locked IdP, failed SSO change, or incident response need can leave teams unable to administer the environment, or relying on shared emergency credentials with poor logging.

Customer-managed key commitments also drift. A provider may market CMK while still holding operational control, support access, or recovery paths that customers do not understand. Contract language, architecture, and evidence need to align.

How to use the paired checklist

Use the checklist to build or validate the shared responsibility matrix first. For each cloud control, identify provider responsibility, customer responsibility, SaaS responsibility, inherited evidence, and configuration evidence.

Attach cloud-native proof: IAM policies, role reviews, network rules, logging settings, encryption configuration, key-management records, backup tests, incident procedures, break-glass logs, and provider assurance documents.

Revisit the checklist after architecture changes. New regions, managed services, CI/CD paths, identity integrations, support models, or key-management options can change the responsibility split and audit evidence.

What teams get wrong

The CSP handles cloud security.
The CSP handles some layers. Customers and SaaS operators still own tenant configuration, IAM, data handling, logging, incident response, and many operational controls.
Customer-managed keys always mean the provider cannot access data.
Key-control claims depend on architecture, support access, recovery design, and contractual commitments. Evidence must match the promise.
ISO 27017 is just ISO 27001 with a cloud badge.
27017 expects cloud-specific responsibility, virtualization, administrator, segregation, monitoring, and customer communication practices.

When the checklist is enough — and when it is not

  • Use the checklist to organize shared responsibility, tenant controls, provider evidence, and cloud security operating records.
  • Ask a certification body, cloud security assessor, or ISO advisor when scope, inherited controls, CMK claims, or audit evidence is unclear.
  • Ask counsel when customer contracts, data access promises, encryption commitments, breach duties, or provider terms are involved.
  • Treat this guide as practical orientation, not official ISO text; use the licensed standard and provider documentation for authoritative requirements.

Related checklists

Related field notes

The checklists and field notes provided on this website are for educational and informational purposes only. They do not constitute legal, financial, or professional advice. Completing a checklist does not guarantee compliance, certification, or immunity from audits. Always consult with a certified auditor or legal counsel for your specific organizational needs. Full disclaimer