The scenario describes a cloud service provider (CSP) that has implemented a robust incident response plan, including specific procedures for handling data breaches involving customer data. ISO 27017:2015, Clause 8.1, “Information security incident management,” mandates that organizations establish and maintain an information security incident management process. This process should include responsibilities, procedures, and reporting mechanisms for handling security incidents, including breaches. Specifically, the standard emphasizes the need for a defined process to assess and respond to security incidents, which naturally extends to data breaches affecting customer data in a cloud environment. The CSP’s proactive approach, involving customer notification and remediation, aligns directly with the principles of effective incident management and the shared responsibility model inherent in cloud computing, as outlined in ISO 27017. The CSP’s actions demonstrate adherence to the requirement for managing security incidents in a way that minimizes impact and fulfills contractual and legal obligations, such as those potentially arising from regulations like GDPR or CCPA, which mandate timely breach notification. The focus on customer data protection and the defined response steps are key indicators of compliance with the spirit and letter of ISO 27017’s incident management controls.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When auditing a cloud service provider (CSP) against this standard, a key consideration is how the CSP manages the shared responsibility model and ensures that customer data remains protected, particularly concerning data deletion and disposal. Clause 7.2.3 of ISO 27017:2015, titled “Protection of information in the cloud,” emphasizes the need for controls to prevent unauthorized disclosure or modification of information. Specifically, when a customer terminates a cloud service, the CSP has an obligation to ensure that the customer’s data is securely disposed of or returned, as per contractual agreements and relevant legal frameworks. This involves not just logical deletion but also ensuring that the underlying physical media is rendered unreadable or destroyed if necessary, to prevent data remanence. The auditor must verify that the CSP’s policies and procedures for data disposal align with industry best practices and regulatory requirements, such as those found in GDPR or similar data protection laws, which mandate secure handling of personal data throughout its lifecycle, including its deletion. Therefore, the most critical aspect for an auditor to verify in this scenario is the CSP’s documented process for secure data deletion and the assurance that this process effectively mitigates the risk of data remanence, thereby fulfilling the CSP’s obligations under ISO 27017 and applicable data protection legislation.

The core of ISO 27017:2015 revolves around shared responsibility in cloud computing security. When a cloud service customer (CSC) utilizes a cloud service provider (CSP), the security controls and responsibilities are divided. ISO 27017 clarifies these responsibilities, particularly concerning data protection and incident management. In the context of a data breach affecting customer data stored in the cloud, the CSC retains ultimate responsibility for the data itself and for notifying affected individuals and relevant authorities, as mandated by regulations like GDPR or CCPA. The CSP, however, has a responsibility to assist the CSC in managing the incident, which includes providing information about the breach’s scope, the affected systems, and any mitigating actions taken by the CSP. This assistance is crucial for the CSC to fulfill its own legal and contractual obligations. Therefore, the CSC’s primary obligation is to manage the overall incident response and stakeholder communication, leveraging the CSP’s support. The CSP’s role is supportive, focusing on the security of the cloud infrastructure and services.

The core of ISO 27017:2015 revolves around the shared responsibility model in cloud computing and the specific controls needed to address cloud-related security risks. When auditing a cloud service provider (CSP) and a cloud service customer (CSC) for compliance with ISO 27017, an auditor must assess how responsibilities are allocated and managed. Specifically, the standard emphasizes the need for clear contractual agreements and documented policies that delineate these responsibilities. For instance, the CSP is typically responsible for the security *of* the cloud infrastructure, while the CSC is responsible for security *in* the cloud, which includes data, access management, and application security.

A critical aspect of an ISO 27017 audit is verifying that both parties understand and adhere to their defined roles. This involves examining evidence of communication, risk assessments, and incident response procedures that reflect the shared responsibility. The standard’s Annex A provides a set of cloud-specific controls that supplement ISO 27002. An auditor would look for evidence that these controls are implemented and that the allocation of responsibility for each control is clearly understood and documented between the CSP and CSC. For example, control A.7.1.1, “Cloud service customer’s responsibilities,” requires the CSC to understand and comply with its responsibilities. Similarly, control A.7.1.2, “Information security roles and responsibilities,” mandates that responsibilities for information security in the cloud are defined and communicated. Therefore, the most effective approach for an auditor to verify compliance in this context is to review the contractual agreements and internal policies of both the CSP and the CSC to ensure a clear and documented delineation of responsibilities for cloud security controls. This directly addresses the foundational principle of shared responsibility as outlined in the standard.

The core of this question lies in understanding the shared responsibility model as defined by ISO 27017:2015, specifically concerning the responsibilities of a Cloud Service Provider (CSP) versus a Cloud Service Customer (CSC) when a security incident impacts a customer’s virtual machine (VM) hosted on the CSP’s infrastructure. ISO 27017 emphasizes that while the CSP is responsible for the security *of* the cloud (i.e., the underlying infrastructure, network, and hypervisor), the CSC is responsible for security *in* the cloud (i.e., the operating system, applications, data, and user access within their VM).

When a security incident, such as unauthorized access, originates from a compromised customer account within a VM, the investigation and remediation efforts primarily fall under the CSC’s purview. This is because the compromise occurred within the customer’s managed environment. The CSP’s role would be to provide necessary logs and support related to the underlying infrastructure if the incident investigation reveals a potential vulnerability or compromise of the CSP’s services. However, the direct management, containment, and eradication of the threat within the VM, including the analysis of the compromised account and its activities, are the CSC’s responsibility.

Therefore, the most appropriate action for the CSC, in this scenario, is to initiate an internal investigation to identify the root cause of the unauthorized access, which would involve analyzing access logs within the VM, reviewing user activity, and potentially isolating the affected VM to prevent further spread. This aligns with the CSC’s responsibility for securing their own data, applications, and operating systems within the cloud environment. The CSP’s obligation is to ensure the integrity of their cloud infrastructure, not to manage the security of individual customer workloads unless the incident directly implicates the CSP’s infrastructure.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing, which dictates how security controls are allocated between the cloud service provider (CSP) and the cloud service customer (CSC). Clause 5.1.1 of ISO 27017, “Responsibilities of cloud service provider and cloud service customer,” is pivotal. It emphasizes that the CSP and CSC must agree on the responsibilities for implementing security controls. This agreement is typically documented in the cloud service agreement (CSA) or a similar contractual document. When a CSC uses a Platform as a Service (PaaS) offering, the CSP manages the underlying infrastructure, operating system, and middleware. The CSC, however, is responsible for securing their applications, data, and user access within that PaaS environment. Therefore, for a PaaS deployment, the CSC is directly responsible for the security of their deployed applications and the data processed by those applications, as well as managing access controls for their users. The CSP is responsible for the security of the underlying platform and infrastructure. The question probes the auditor’s understanding of this division of responsibility in a PaaS context, specifically concerning the security of the customer’s deployed applications and data. The correct option reflects the CSC’s direct accountability for these elements within the PaaS model, aligning with the principles of shared responsibility as defined by the standard.

The scenario describes a cloud service provider (CSP) offering Infrastructure as a Service (IaaS) and Platform as a Service (PaaS) to a customer. The customer is responsible for securing the operating system and above, while the CSP is responsible for the underlying infrastructure. ISO 27017:2015, specifically Clause 5.3.1, addresses the responsibilities of cloud service providers and cloud customers. It mandates that the responsibilities for information security controls should be clearly defined and communicated. In this context, the CSP must ensure that its responsibilities for the physical security of the data center, network infrastructure, and hypervisor layer are documented and communicated to the customer. This communication is crucial for establishing a shared understanding of security obligations and ensuring that no critical security controls are overlooked due to a gap in responsibility. Therefore, the most appropriate action for the auditor to verify the CSP’s adherence to ISO 27017:2015, particularly regarding the defined responsibilities, is to examine the contractual agreements and service level agreements (SLAs) that explicitly delineate these shared security duties. These documents serve as the formal record of the agreed-upon security responsibilities between the CSP and the customer, directly reflecting the requirements of the standard.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When a cloud service customer (CSC) is migrating sensitive data, the responsibility for implementing specific security controls becomes a critical point of discussion and agreement between the CSC and the cloud service provider (CSP). ISO 27017 emphasizes the shared responsibility model. In this context, the CSC retains ultimate responsibility for the security of its data, even when it resides within the CSP’s infrastructure. Therefore, the CSC must ensure that the CSP’s security measures, as documented in their service level agreements (SLAs) and relevant policies, adequately protect the sensitive data. This includes verifying that the CSP has implemented controls that align with the CSC’s risk assessment and regulatory obligations, such as those mandated by GDPR or HIPAA, if applicable. The CSC cannot simply delegate its entire security burden to the CSP; it must actively manage the security of its data by selecting a CSP that meets its security requirements and by understanding the division of responsibilities for each control. The CSC’s due diligence in selecting a compliant CSP and its ongoing monitoring of the CSP’s adherence to security commitments are paramount.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing, which dictates how security controls are allocated between the cloud service provider (CSP) and the cloud service customer (CSC). When a CSC uses a Platform as a Service (PaaS) offering, the CSP is responsible for the security *of* the cloud, encompassing the underlying infrastructure, network, and the platform itself. The CSC, however, retains responsibility for security *in* the cloud, which includes the applications they deploy, the data they store, and how they configure and manage the platform services. Specifically, in a PaaS model, the CSP manages the operating system, middleware, and runtime environments. The CSC is accountable for securing their applications, data, access controls, and any configurations they make to the PaaS environment that could impact security. Therefore, when auditing a CSC’s PaaS usage, the auditor must focus on the CSC’s responsibilities, such as their application security testing, data encryption practices, and identity and access management for users accessing the PaaS. The CSP’s adherence to ISO 27017 controls related to the infrastructure and platform itself would be verified through the CSP’s own certifications and audit reports, not directly by auditing the CSC’s implementation.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When a cloud service customer (CSC) intends to use a cloud service provider (CSP) for processing sensitive data, the responsibility for implementing specific security controls is a shared one, defined by the service model (IaaS, PaaS, SaaS) and the contractual agreement. ISO 27017 emphasizes the importance of clearly defining these responsibilities. In the context of a CSC using IaaS, the CSP is typically responsible for the security *of* the cloud infrastructure (e.g., physical security of data centers, network infrastructure). The CSC, however, is responsible for security *in* the cloud, which includes configuring virtual machines, managing operating systems, applications, and data. Therefore, when auditing a CSC’s use of IaaS, the auditor must verify that the CSC has implemented appropriate controls for the components they manage, such as secure configuration of virtual network interfaces, access control to virtual machines, and data encryption at rest and in transit for data stored within the IaaS environment. The CSP’s responsibilities are verified through their own certifications and attestations, which the CSC should leverage. The question probes the auditor’s understanding of where the CSC’s direct responsibility lies in an IaaS model, specifically concerning the security of the underlying cloud infrastructure itself, which is primarily the CSP’s domain. The correct approach focuses on the CSC’s management of their deployed resources and data, not the fundamental security of the CSP’s physical or network infrastructure.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When auditing a cloud service provider (CSP) against this standard, a crucial aspect is verifying the CSP’s adherence to the shared responsibility model. Specifically, the CSP is responsible for the security *of* the cloud, while the customer is responsible for security *in* the cloud. Clause 7.1.1 of ISO 27017, “Cloud service provider’s responsibilities,” directly addresses this by outlining the CSP’s obligations. A key element of these obligations is the provision of a clear and documented statement of responsibilities that delineates what the CSP manages versus what the customer must manage. This statement is fundamental for ensuring that both parties understand their security duties, preventing gaps in security coverage, and enabling effective auditing. Without this explicit delineation, it becomes impossible to verify that the CSP is meeting its obligations as defined by the standard, particularly concerning the controls it directly manages and the transparency it provides to customers regarding their own security responsibilities. Therefore, the absence of a documented shared responsibility model statement would be a significant non-conformity.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services, building upon ISO 27002. When a cloud service customer (CSC) is migrating sensitive data to a cloud service provider (CSP), the responsibility for implementing specific security controls is often shared. ISO 27017 clarifies these shared responsibilities. Specifically, for controls related to the protection of information in transit (e.g., encryption of data during transmission), the CSC retains the primary responsibility for ensuring that appropriate encryption mechanisms are in place for data being sent to and from the cloud. While the CSP might provide the underlying network infrastructure and potentially offer encryption services, the CSC must configure and manage these services to meet their specific security requirements and risk appetite. This includes selecting appropriate encryption algorithms, managing keys, and ensuring the secure transmission of data to the cloud environment. Therefore, the CSC is accountable for the security of data in transit to the cloud.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing, which dictates how security controls are allocated between the cloud service provider (CSP) and the cloud service customer (CSC). When a CSC utilizes a Platform as a Service (PaaS) offering, the CSP is responsible for the security *of* the cloud infrastructure, including the underlying hardware, networking, and operating systems. The CSC, however, retains responsibility for security *in* the cloud, which encompasses their data, applications, identity and access management, and the configuration of the PaaS environment itself. Specifically, for a PaaS model, the CSP manages the runtime, middleware, and operating system. The CSC is accountable for securing their deployed applications, managing user access to those applications, and ensuring the confidentiality, integrity, and availability of their data stored or processed within the PaaS environment. Therefore, when auditing a CSC’s use of PaaS, the auditor must focus on the CSC’s controls related to application security, data protection, and access management, as these are areas where the CSC has direct and primary responsibility under the shared responsibility model as defined by ISO 27017:2015. The CSP’s responsibilities are typically covered by their own certifications and audits, but the CSC’s adherence to their part of the model is crucial for overall cloud security.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When a cloud service customer (CSC) delegates responsibilities to a cloud service provider (CSP) for specific security controls, the CSC retains overall accountability. This means the CSC must ensure that the controls implemented by the CSP meet the CSC’s own security requirements and any applicable legal or regulatory obligations. The standard emphasizes the importance of a clear agreement, often through a cloud service agreement or contract, that defines the responsibilities of both parties. This agreement should explicitly state which controls are managed by the CSP and which remain the responsibility of the CSC. For instance, if the CSC is responsible for data classification and access management policies, even if the CSP provides the underlying infrastructure, the CSC must verify that the CSP’s services support these policies. The CSC’s audit process must therefore focus on validating the CSP’s adherence to the agreed-upon responsibilities and ensuring that the residual risks are acceptable. This involves reviewing the CSP’s security policies, procedures, and audit reports, as well as potentially conducting direct assessments where permitted. The principle is that while the CSP implements and operates controls, the CSC remains the ultimate guardian of its data and must demonstrate due diligence in ensuring its security within the cloud environment.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When a cloud service customer (CSC) is responsible for managing certain aspects of the cloud service, and the cloud service provider (CSP) is responsible for others, a clear delineation of responsibilities is paramount. This is particularly true for incident management. According to ISO 27017:2015, specifically in Annex A, control A.12.4.1, “Management of information security incidents and improvements,” the CSC should have defined procedures for reporting and responding to security incidents. However, the CSP plays a crucial role in facilitating this by providing mechanisms for the CSC to report incidents affecting the cloud service. The CSP’s responsibility extends to informing the CSC about incidents that impact the CSC’s data or services hosted within the cloud environment. Therefore, the most appropriate action for the CSC, when discovering a potential security incident within the cloud service that appears to be related to the CSP’s infrastructure, is to initiate the reporting process to the CSP. This ensures that the CSP is aware and can take appropriate action within their scope of responsibility, while also allowing the CSC to fulfill its own incident management obligations. The other options represent either a premature escalation without proper notification, an abdication of responsibility, or an action that bypasses the necessary communication channels defined by the standard for shared responsibility models.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When auditing a cloud service provider (CSP) regarding their adherence to ISO 27017, a critical aspect is verifying the CSP’s responsibility for data deletion and destruction. Clause 6.3.1 of ISO 27017 specifically addresses the “Information deletion” control. This control mandates that the CSP should ensure that information is deleted or destroyed when it is no longer required for business or legal purposes. For an auditor, verifying this involves examining the CSP’s policies, procedures, and technical mechanisms for data sanitization and destruction. This includes understanding how data is securely removed from storage media, whether physical or virtual, and ensuring that remnants of data are rendered unrecoverable. The auditor would look for evidence of secure deletion methods (e.g., cryptographic erasure, overwriting) and confirmation that these methods are applied consistently across all cloud service offerings and underlying infrastructure. The audit would also consider the CSP’s contractual obligations to the customer regarding data retention and deletion timelines, as well as any legal or regulatory requirements that might mandate specific data destruction practices. Therefore, the most appropriate audit objective for a cloud security auditor, in this context, is to confirm the CSP’s documented and implemented procedures for secure data deletion and destruction, aligning with the requirements of ISO 27017 and relevant legal frameworks.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When auditing a cloud service provider (CSP) against this standard, a crucial aspect is verifying the CSP’s adherence to the shared responsibility model. This model dictates that both the CSP and the customer have distinct security responsibilities. For a CSP offering Infrastructure as a Service (IaaS), the CSP is typically responsible for the security *of* the cloud (e.g., physical security of data centers, network infrastructure, hypervisor security), while the customer is responsible for security *in* the cloud (e.g., operating system patching, application security, data encryption, access control for virtual machines).

A cloud security auditor must assess whether the CSP has clearly documented and communicated these responsibilities to its customers. This includes ensuring that the CSP’s service level agreements (SLAs) and contractual terms accurately reflect the division of responsibilities as per ISO 27017:2015. Specifically, the auditor would look for evidence that the CSP has implemented controls to protect the underlying cloud infrastructure and that these controls are demonstrably effective. Furthermore, the auditor needs to verify that the CSP provides mechanisms and information to enable customers to fulfill their respective responsibilities. This might involve providing security configuration guides, audit logs of the CSP’s infrastructure, and clear reporting on security incidents affecting the cloud service. The auditor’s objective is to confirm that the CSP’s security posture, as it pertains to the shared responsibility model, aligns with the requirements and recommendations of ISO 27017:2015, ensuring that no critical security gaps arise due to misaligned responsibilities.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing, which dictates how security controls are allocated between the cloud service provider (CSP) and the cloud service customer (CSC). When a CSC utilizes a Platform as a Service (PaaS) offering, the CSP is responsible for the security *of* the cloud infrastructure, including the underlying hardware, networking, and the operating system/middleware. The CSC, however, retains responsibility for security *in* the cloud, which encompasses their data, applications, identity and access management, and the configuration of the PaaS environment itself. Specifically, the CSC is accountable for ensuring that the deployed applications are secure, that access to these applications and the data they process is appropriately managed, and that any configurations within the PaaS environment (e.g., network security groups, database access controls) are correctly implemented and maintained. The shared responsibility model is not static; it shifts based on the cloud service model (IaaS, PaaS, SaaS). For PaaS, the boundary of responsibility is more nuanced than IaaS but less encompassing for the CSC than SaaS. Therefore, the CSC must focus on securing their own assets and configurations within the provided platform, rather than the platform’s foundational security.

The core principle being tested here is the auditor’s responsibility in assessing a cloud service provider’s (CSP) adherence to ISO 27017:2015, specifically concerning the shared responsibility model and the demarcation of controls. When auditing a CSP, the auditor must verify that the CSP has clearly defined and communicated its responsibilities for security controls, particularly those that are shared or are the customer’s responsibility. This involves examining documentation, policies, and contractual agreements to ensure that the customer is adequately informed about their own security obligations. A key aspect of ISO 27017 is the guidance on the responsibilities of both the cloud service customer and the cloud service provider. The auditor’s role is to confirm that the CSP has fulfilled its part in this shared model, which includes providing clarity on what the customer must implement. Therefore, the auditor’s primary focus should be on the CSP’s documented approach to defining and communicating these shared responsibilities, ensuring that the customer has the necessary information to implement their part of the security framework. This directly aligns with the intent of ISO 27017 to provide a framework for cloud security that acknowledges the distributed nature of responsibilities.

The core principle being tested here is the auditor’s responsibility in assessing a cloud service provider’s (CSP) adherence to ISO 27017:2015, specifically concerning the shared responsibility model and the demarcation of controls. When auditing a CSP, an auditor must verify that the CSP has clearly documented and communicated its responsibilities for security controls, especially those that are shared with the customer. This includes controls related to the physical security of data centers, network infrastructure, and the underlying hypervisor layer, which are typically managed by the CSP. The auditor’s role is to ensure that the CSP’s controls are effectively implemented and that the CSP has provided sufficient evidence of this implementation. The question probes the auditor’s focus on the CSP’s direct control implementation and its documentation, rather than the customer’s specific configuration or usage of the cloud service, which falls under the customer’s responsibility. Therefore, the auditor’s primary concern is the CSP’s documented and implemented controls for the infrastructure and platform services it provides, ensuring these align with the standard’s requirements for shared responsibility.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When a cloud service customer (CSC) is responsible for managing certain aspects of the cloud service, and the cloud service provider (CSP) is responsible for others, the delineation of responsibilities is paramount. Clause 6.3.1 of ISO 27017 specifically addresses the responsibilities for information security in the cloud computing environment. It emphasizes that both the CSC and CSP must understand and agree upon their respective roles and responsibilities. This agreement is typically formalized through a cloud service agreement or contract.

In the scenario presented, the CSC is migrating sensitive customer data to a Platform as a Service (PaaS) offering. The PaaS model inherently means the CSP manages the underlying infrastructure, operating system, and middleware. However, the CSC retains responsibility for the data itself, application security, and user access management. Therefore, the CSC’s audit focus should be on how the CSP’s controls, as defined in their service agreement and security documentation, align with the CSC’s own security requirements and the principles of ISO 27017. Specifically, the CSC needs to verify that the CSP has implemented appropriate controls for the shared responsibility model, particularly concerning data protection, access control to the PaaS environment, and incident management related to the platform. The audit should confirm that the CSP’s security posture supports the CSC’s compliance obligations, such as those mandated by regulations like GDPR or CCPA, which require robust data protection measures. The audit should not solely focus on the CSC’s internal controls, as that would ignore the CSP’s critical role in the PaaS environment. Similarly, an audit solely on the CSP’s internal operations without considering the CSC’s specific data and application context would be incomplete. The most effective approach is to assess the integration of CSP controls with CSC responsibilities within the contractual framework.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When a cloud service customer (CSC) is migrating sensitive data, the responsibility for implementing and managing specific security controls shifts between the CSC and the cloud service provider (CSP). ISO 27017:2015 emphasizes the shared responsibility model. Specifically, for data encryption at rest and in transit, the CSC typically retains the primary responsibility for defining the encryption requirements, managing the encryption keys, and ensuring the overall effectiveness of the encryption strategy, even though the CSP provides the underlying infrastructure that supports these operations. The CSP’s role is to provide a secure environment and the necessary cryptographic services or capabilities, but the ultimate control and management of keys and the decision on encryption algorithms and policies usually rest with the customer for sensitive data. Therefore, the CSC is responsible for ensuring that the encryption mechanisms employed meet their specific security and compliance needs, which often involves key management practices that are outside the direct operational control of the CSP. This aligns with the principle that the entity processing or storing the sensitive data has the ultimate accountability for its protection.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing, which dictates how security controls are allocated between the cloud service provider (CSP) and the cloud service customer (CSC). When a CSC uses a Platform as a Service (PaaS) offering, the CSP is responsible for the security *of* the cloud infrastructure, including the underlying hardware, networking, and hypervisor. The CSC, however, is responsible for security *in* the cloud, which encompasses their data, applications, operating systems, identity and access management, and network configurations within the PaaS environment.

Consider a scenario where a CSC is using a PaaS offering for a web application. The CSP manages the virtual machines, storage, and networking infrastructure. The CSC deploys their application code, configures the operating system’s security settings (if exposed), manages user access to the application, and encrypts their data. If a vulnerability is discovered in the CSP’s hypervisor, it is the CSP’s responsibility to patch it, as it falls under “security of the cloud.” Conversely, if the CSC’s application code contains a SQL injection vulnerability, the CSC is responsible for fixing it, as it falls under “security in the cloud.”

Therefore, in a PaaS model, the responsibility for securing the operating system’s configuration and patching vulnerabilities within that operating system rests with the cloud service customer, as it is part of the environment they manage and deploy applications onto. The cloud service provider’s responsibility typically ends at the abstraction layer provided by the PaaS.

The core of ISO 27017:2015, particularly concerning the responsibilities of cloud service customers, is the principle of shared responsibility. When a cloud service provider (CSP) offers Infrastructure as a Service (IaaS), the customer is responsible for a significant portion of the security stack, including operating systems, middleware, and applications. ISO 27017:2015 Clause 6.3.1, “Responsibilities of cloud service customer,” emphasizes that the customer must implement security controls for the services they manage. In an IaaS model, this extends to securing the virtual network configuration, including firewall rules, intrusion detection/prevention systems (IDPS) deployed within the customer’s virtual environment, and the secure configuration of operating systems and applications. The CSP is responsible for the security *of* the cloud, meaning the underlying physical infrastructure and the virtualization layer. The customer is responsible for security *in* the cloud. Therefore, a customer auditing an IaaS provider must verify that the provider has controls for the foundational layers, while also ensuring the customer has implemented robust controls for the layers they manage, such as application-level security and data encryption. The question probes the auditor’s understanding of where the customer’s responsibility begins in an IaaS context, specifically regarding network segmentation and access control within the virtualized environment. The correct approach involves identifying controls that are demonstrably within the customer’s purview in an IaaS setup, such as the configuration of virtual firewalls and the management of virtual network interfaces.

The core principle being tested here is the auditor’s responsibility in verifying the implementation of security controls related to data deletion and disposal in a cloud environment, specifically within the context of ISO 27017:2015. The standard emphasizes that cloud service customers (CSCs) are responsible for the data they entrust to cloud service providers (CSPs). However, ISO 27017 also places obligations on CSPs regarding data deletion and disposal, which the CSC must be able to verify. An auditor’s role is to confirm that the CSP has implemented mechanisms to ensure data is irretrievably deleted upon the CSC’s request or at the end of the service contract, and that this process is documented and auditable. This involves checking the CSP’s policies, procedures, and technical controls for data sanitization and destruction, ensuring they align with the agreed-upon service level agreements (SLAs) and relevant data protection regulations, such as GDPR or CCPA, which mandate secure data deletion. The auditor must confirm that the CSP provides assurance to the CSC that data is no longer accessible or recoverable, and that this assurance is supported by evidence. Therefore, the most appropriate action for the auditor is to review the CSP’s documented procedures for secure data deletion and verify their effective implementation through evidence, such as logs or certifications, that demonstrate the data has been rendered unrecoverable. This approach directly addresses the shared responsibility model and the specific controls outlined in ISO 27017 for data lifecycle management in the cloud.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing and how controls are applied within this context. When a cloud service customer (CSC) uses a cloud service provider (CSP), certain security responsibilities are retained by the CSC, while others are managed by the CSP. ISO 27017 provides guidance on how to map controls from ISO 27002 to the cloud environment, considering these shared responsibilities. Specifically, the standard emphasizes that even for controls managed by the CSP, the CSC retains the responsibility for ensuring the effectiveness of those controls through appropriate contractual agreements and monitoring. The question probes the auditor’s understanding of where the ultimate accountability for the implementation and operation of specific security controls lies within the shared responsibility framework, particularly concerning data protection and access management. An auditor must verify that the CSC has adequately addressed its responsibilities, which includes ensuring the CSP’s controls meet the CSC’s security requirements, even if the CSP directly implements them. This involves reviewing contracts, service level agreements (SLAs), and audit reports from the CSP, as well as the CSC’s own internal processes for managing these outsourced functions. Therefore, the CSC’s responsibility extends to verifying the CSP’s adherence to security commitments, not just the controls it directly manages.

The core of ISO 27017:2015 is the shared responsibility model in cloud computing, which dictates how security controls are allocated between the cloud service provider (CSP) and the cloud service customer (CSC). When a CSC uses a Platform as a Service (PaaS) offering, the CSP is responsible for the security *of* the cloud, encompassing the underlying infrastructure, network, and the operating system. The CSC, however, is responsible for security *in* the cloud, which includes the applications they deploy, the data they store, user access management, and the configuration of the PaaS environment itself. Specifically, the CSC must ensure that their deployed applications are secure, that data is classified and protected according to its sensitivity, and that access to these applications and data is properly managed through identity and access management (IAM) controls. Furthermore, the CSC is accountable for the security configurations of the PaaS services they utilize, such as database security settings or API gateway policies. Therefore, in a PaaS scenario, the responsibility for securing the deployed application code and managing user access to that application rests squarely with the cloud service customer.

The core principle being tested here is the shared responsibility model in cloud computing, specifically as it pertains to ISO 27017:2015. When a cloud service provider (CSP) offers Infrastructure as a Service (IaaS), the CSP is responsible for the security *of* the cloud, which includes the underlying physical infrastructure, network, and hypervisor. The customer, however, is responsible for security *in* the cloud. This encompasses the operating system, middleware, applications, and data deployed on the IaaS. Therefore, in an IaaS scenario, the CSP is not directly responsible for the configuration and patching of the virtual machines’ operating systems, nor for the security of the data stored within those VMs, nor for the access controls applied to the applications running on them. These are all within the customer’s purview. The question asks what the CSP is *not* responsible for in this context. The correct answer identifies an area that falls squarely under the customer’s responsibility in an IaaS model according to the shared responsibility framework that ISO 27017 builds upon.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services. When auditing a cloud service provider (CSP) against this standard, a key consideration is how the CSP manages the shared responsibility model. Specifically, the CSP must demonstrate that it has implemented appropriate controls for the aspects of the cloud service that remain under its purview, even when the customer is responsible for other aspects. This involves verifying that the CSP’s security policies, procedures, and technical controls align with the requirements of ISO 27001 and the specific cloud security controls outlined in ISO 27017. A critical audit activity is to assess the CSP’s documented responsibilities and how these are communicated to customers, ensuring transparency and clarity regarding the division of security duties. This includes examining contractual agreements, service level agreements (SLAs), and any accompanying security addendums or policies that define the security obligations of both parties. The auditor must verify that the CSP’s internal processes for managing these responsibilities are effective and that there are mechanisms in place to address any gaps or misinterpretations of the shared responsibility model. For instance, the CSP should have a process for reviewing and updating its shared responsibility documentation based on changes in its services or evolving threat landscapes. The auditor would look for evidence of this proactive management.

The core of ISO 27017:2015 is to provide guidance on the information security aspects of cloud computing. When auditing a cloud service provider (CSP) for compliance, a key area of focus is the CSP’s responsibility for implementing controls that protect customer data in the cloud. Specifically, Clause 6.3.1 of ISO 27017 addresses the “Information security in the development and maintenance of cloud services.” This clause emphasizes that CSPs should ensure that security is integrated throughout the entire lifecycle of their cloud services. This includes secure coding practices, vulnerability management in development, and ensuring that the underlying infrastructure supporting the cloud service is also secured.

A cloud auditor must verify that the CSP has established and maintains a process for managing security during the development and ongoing maintenance of their cloud services. This involves reviewing documentation, interviewing personnel, and potentially observing practices related to secure software development lifecycle (SSDLC) methodologies, change management processes that incorporate security reviews, and incident response planning that accounts for vulnerabilities discovered in deployed services. The auditor’s objective is to confirm that the CSP proactively identifies, assesses, and mitigates security risks associated with their service offerings, rather than relying solely on reactive measures. This proactive approach is fundamental to demonstrating a commitment to cloud security as mandated by the standard.