The core of ISO 27017:2015 revolves around the shared responsibility model in cloud computing and the specific controls that address cloud service security. When a cloud service customer (CSC) utilizes a cloud service provider (CSP), the responsibilities for security are divided. ISO 27017 provides guidance on which party is typically responsible for specific security controls. Control 5.1.1, “Information security policies,” is fundamental. In a cloud context, the CSP is primarily responsible for establishing and maintaining its own information security policies that govern the cloud service itself, including the infrastructure and the security of the data processed within it. The CSC, in turn, is responsible for defining and implementing its own information security policies that apply to its use of the cloud service, including data classification, access control for its users, and the security of its own applications and data deployed on the cloud. Therefore, the CSP’s responsibility for establishing policies directly related to the cloud service’s security posture is paramount.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, the responsibility for security is divided between the cloud service provider (CSP) and the CSC. ISO 27017:2015, Clause 5.1.1, “Roles and responsibilities,” emphasizes the need for clear definition and documentation of these roles. Specifically, the CSC is responsible for the security of data processed within the cloud service and for the configuration and management of security controls related to their specific use of the service. This includes aspects like access control to their data, encryption of data at rest and in transit where applicable to their data, and the security of their own endpoints and user management. The CSP, conversely, is responsible for the security of the underlying cloud infrastructure and the services provided. Therefore, in the scenario described, the CSC’s failure to implement appropriate access controls for their sensitive customer data, which is stored within the cloud environment, directly falls under their purview of responsibility as defined by the standard. The breach resulting from this oversight is a direct consequence of the CSC’s inadequate security practices concerning their own data and its access mechanisms.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services, building upon ISO 27002. It addresses the shared responsibility model inherent in cloud computing. When a cloud service customer (CSC) utilizes a cloud service provider (CSP), certain security responsibilities are transferred or shared. The standard emphasizes that the CSC retains ultimate responsibility for the security of their data and systems, even when hosted in the cloud. This includes ensuring appropriate controls are in place for data classification, access management, and incident response, even if the underlying infrastructure is managed by the CSP. The CSP, in turn, is responsible for the security *of* the cloud, such as the physical security of data centers and the security of the cloud infrastructure itself. Therefore, a CSC must understand which controls are managed by the CSP and which remain their responsibility. This understanding is crucial for effective risk management and compliance with regulations like GDPR or HIPAA, which mandate data protection regardless of the hosting environment. The CSC’s due diligence involves verifying the CSP’s security posture and ensuring that the shared responsibilities align with their own security requirements and legal obligations.

The core principle being tested here is the shared responsibility model in cloud computing, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are inherently retained by the CSC, regardless of the cloud service model (IaaS, PaaS, SaaS). ISO 27017 emphasizes that the CSC is accountable for managing and securing data within the cloud environment, including access control to that data, the configuration of security settings related to data protection, and the overall security posture of their applications and workloads deployed in the cloud. The cloud service provider (CSP) is responsible for the security *of* the cloud infrastructure itself. Therefore, the CSC’s responsibility for the security of their data, including its classification, encryption, and access management, remains paramount. This aligns with the fundamental understanding that while the CSP provides the secure environment, the CSC must secure what they place within that environment. The other options represent responsibilities that typically fall under the CSP’s purview, such as the physical security of data centers, the security of the underlying network infrastructure, or the secure development of the cloud platform itself.

The core principle being tested here is the distinction between a customer’s responsibility for data security in the cloud and the cloud service provider’s (CSP) responsibility for the security *of* the cloud. ISO 27017:2015, specifically in Annex A, outlines shared responsibilities. When a customer utilizes a Platform as a Service (PaaS) offering, the CSP is responsible for the underlying infrastructure, operating system, and middleware. The customer, however, retains responsibility for the security of their data, applications, and configurations within that PaaS environment. This includes implementing appropriate access controls, encryption for data at rest and in transit, and ensuring the secure development and deployment of their applications. A breach originating from misconfigured access controls on user accounts within the customer’s deployed application, or from unpatched vulnerabilities in custom code deployed by the customer, falls squarely within the customer’s domain of responsibility. Therefore, the scenario described, where unauthorized access is gained through compromised customer-managed credentials for a specific application deployed on PaaS, is a direct consequence of the customer’s failure to adequately secure their own data and application configurations, aligning with their defined responsibilities under ISO 27017.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the cloud service provider (CSP), while others are transferred to or shared with the CSC. ISO 27017:2015, in its guidance on responsibilities, emphasizes that the CSC is accountable for the security of data it processes within the cloud environment, including the configuration and management of virtual machines, operating systems, and applications deployed on the cloud infrastructure. This includes implementing appropriate access controls, vulnerability management for the software stack they manage, and ensuring the confidentiality, integrity, and availability of their data. The CSP, conversely, is responsible for the security *of* the cloud, which encompasses the underlying infrastructure, physical security of data centers, and the security of the cloud platform itself. Therefore, when considering the security of sensitive customer data stored in a cloud database, the responsibility for securing the database configuration, access policies, and the data itself rests with the CSC, assuming the CSP provides a secure underlying platform. This aligns with the principle that the CSC must manage the security of its own data and applications, even when hosted by a CSP.

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 and managing specific security controls is a shared one, determined by the nature of the service and the contractual agreement. ISO 27017 emphasizes the need for clear delineation of responsibilities. In this scenario, the CSC retains ultimate accountability for the data’s security, including the classification and protection of that data. While the CSP is responsible for the security *of* the cloud infrastructure and services (e.g., physical security of data centers, network security of the cloud platform), the CSC is responsible for security *in* the cloud, which includes configuring access controls, managing user identities, encrypting data at rest and in transit, and ensuring compliance with relevant regulations like GDPR or HIPAA for their specific data. Therefore, the CSC must ensure that the CSP’s controls adequately support the CSC’s own security requirements and legal obligations. The selection of a CSP that can meet these requirements, and the ongoing monitoring of that compliance, falls squarely on the CSC. The CSP’s role is to provide a secure environment and services, but the CSC must actively manage its own security posture within that environment.

The core principle tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are inherently retained by the CSC, regardless of the cloud service provider’s (CSP) overall security posture. ISO 27017 emphasizes that the CSC is responsible for managing the security of the data it stores and processes within the cloud environment, as well as the security of the applications and configurations it deploys. This includes aspects like access control to data, encryption of data at rest and in transit where applicable to the CSC’s data, and the secure configuration of virtual machines or containers. The CSP, conversely, is responsible for the security *of* the cloud infrastructure itself, such as the physical security of data centers, the network infrastructure, and the hypervisor layer. Therefore, a breach originating from misconfigured user access controls or unpatched application vulnerabilities within the CSC’s deployed virtual machine directly falls under the CSC’s purview, even if the underlying infrastructure is managed by the CSP. This distinction is crucial for understanding liability and implementing appropriate security measures.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the cloud service provider (CSP), while others are transferred to or shared with the CSC. ISO 27017:2015, in its Annex A controls, outlines specific responsibilities. Control A.6.1.1, “Roles and responsibilities,” is fundamental. In the context of a cloud service, the CSP is responsible for the security *of* the cloud infrastructure (e.g., physical security of data centers, network infrastructure security, hypervisor security). The CSC, however, is responsible for security *in* the cloud, which includes their data, applications, operating systems (if applicable in IaaS), and user access management. When a CSC experiences a data breach originating from a misconfigured access control list (ACL) on their virtual machine’s storage, this falls squarely within the CSC’s domain of responsibility. The CSP provides the underlying infrastructure and the tools to manage it, but the CSC must configure these tools correctly. Therefore, the CSC is accountable for rectifying the breach and implementing controls to prevent recurrence, such as enhancing access management policies and conducting regular security audits of their configurations. The CSP’s role would be to provide support and potentially forensic data if requested and contractually agreed upon, but not to directly remediate the CSC’s misconfiguration.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the cloud service provider (CSP), while others are transferred to the CSC. ISO 27017:2015, in Annex A, outlines controls applicable to both CSPs and CSCs. Control A.6.1.1, “Information security policies,” mandates that both parties establish and maintain information security policies. However, the specific implementation details and the responsibility for defining the *scope and purpose* of the cloud service’s information security, including the classification of data and the establishment of security objectives, primarily fall under the CSC’s purview, as they are the data owner and the entity with the ultimate business need. The CSP provides the infrastructure and services, and their policies must align with the CSC’s requirements, but the foundational definition of what needs to be secured and why rests with the customer. Therefore, the CSC is responsible for defining the information security requirements for the cloud service, which encompasses the classification of information, the establishment of security objectives, and the overall governance framework for data protection within the cloud environment. This aligns with the CSC’s role as the data controller or processor, depending on the specific context and applicable regulations like GDPR.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017:2015. When a cloud service customer (CSC) utilizes Infrastructure as a Service (IaaS), the cloud service provider (CSP) is responsible for the security *of* the cloud, which includes the underlying infrastructure, physical security of data centers, and the hypervisor. The CSC, however, is responsible for security *in* the cloud, encompassing the operating system, applications, data, identity and access management, and network configurations within their virtual environment. ISO 27017:2015, by extending ISO 27001 with cloud-specific controls, clarifies these responsibilities. Control A.7.1.1 (Inventory of information and other associated assets) and A.7.2.1 (Identification of assets) are crucial for the CSC to understand what they are responsible for securing within their IaaS deployment. A CSP’s responsibility for vulnerability management typically extends to the foundational layers they manage, not necessarily the customer’s deployed operating systems or applications. Therefore, the CSC must implement its own vulnerability management program for the components it controls.

The core of this question revolves around the shared responsibility model in cloud computing, specifically as it pertains to ISO 27017. 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, in this case, is responsible for security *in* the cloud, which encompasses the operating system, applications, data, and identity and access management within their virtualized environment. ISO 27017 provides guidance on controls applicable to both cloud service providers and cloud service customers. For an IaaS offering, the CSP’s obligation regarding the security of the underlying network infrastructure is a fundamental aspect of their service. This includes ensuring the integrity and availability of the network components that enable connectivity to and within the cloud environment. The customer, while responsible for configuring their virtual network security groups and firewalls, relies on the CSP to provide a secure and functional physical and logical network foundation. Therefore, the CSP’s responsibility for the security of the network infrastructure itself, as a component of the cloud, is paramount.

The core principle being tested here is the shared responsibility model in cloud computing, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the CSC, while others are managed by the cloud service provider (CSP). ISO 27017:2015, in its guidance on information security controls for cloud services, emphasizes that the CSC is ultimately accountable for the security of their data and the configuration of their cloud environment, even when leveraging CSP services. This includes responsibilities related to access control, data encryption, and the secure configuration of virtual machines and containers. The CSP is responsible for the security *of* the cloud infrastructure itself, such as the physical security of data centers, network infrastructure, and the hypervisor layer. Therefore, when a CSC experiences a data breach due to misconfigured access controls on a virtual machine instance they are managing, the responsibility for the breach lies with the CSC because the misconfiguration falls under their purview of control and management, as defined by the shared responsibility model and reinforced by ISO 27017’s control objectives. The standard does not absolve the CSC of responsibility for their own operational security practices within the cloud environment.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the cloud service provider (CSP), while others are transferred to or shared with the CSC. ISO 27017:2015, in Annex A, outlines controls applicable to both CSPs and CSCs. Control A.5.1.1, “Information security policies,” mandates that policies address the roles and responsibilities of both parties. Control A.6.1.1, “Information security roles and responsibilities,” further elaborates on defining these roles. In the context of a data breach affecting customer data stored in the cloud, the CSC is fundamentally responsible for the security of its data and the access controls to that data. While the CSP is responsible for the security *of* the cloud infrastructure, the CSC is responsible for the security *in* the cloud. This includes implementing appropriate access controls, encryption, and data classification for the data it entrusts to the CSP. Therefore, the CSC bears the primary responsibility for ensuring its data is protected from unauthorized access and disclosure, even if the breach originated from a vulnerability within the CSP’s infrastructure, as the CSC’s own security posture regarding data handling and access management is paramount. The CSC’s obligation extends to understanding and managing the risks associated with the cloud service, including the potential impact of CSP-related security incidents on its data.

The core principle being tested here is the shared responsibility model in cloud computing, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service from a cloud service provider (CSP), certain security responsibilities are inherently retained by the CSC, regardless of the CSP’s security measures. ISO 27017:2015, Clause 5.2.1, emphasizes the need for the CSC to understand and manage its responsibilities. Specifically, the CSC is responsible for the security of data it processes and stores within the cloud environment, including the configuration of access controls, encryption of data at rest and in transit, and managing user identities and privileges. The CSP is responsible for the security *of* the cloud infrastructure itself. Therefore, if a data breach occurs due to misconfigured access controls by the CSC, or due to the CSC failing to implement appropriate encryption for sensitive data it uploads, the CSC bears the primary responsibility for that specific incident, even though the CSP provides the underlying secure infrastructure. This aligns with the principle that the CSC must implement controls relevant to its specific use of the cloud service.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service provider (CSP) offers Platform as a Service (PaaS), the CSP is responsible for the security *of* the cloud infrastructure, including the underlying hardware, networking, and hypervisor. The customer, in this case, 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. ISO 27017 emphasizes the need for clear delineation of these responsibilities. Therefore, the customer’s responsibility for securing the operating system and the applications deployed on it, along with managing user access and data protection, aligns with the customer’s role in a PaaS model. The CSP’s responsibility for the underlying infrastructure, such as the physical security of data centers and the network fabric, is also a key aspect of the shared model. The question probes the understanding of where the customer’s accountability begins and ends within the PaaS context, as guided by ISO 27017 principles.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services, building upon ISO 27002. When a customer (user entity) transitions from a traditional on-premises environment to a cloud service, the responsibility for certain security controls shifts. ISO 27017 clarifies these shared responsibilities. Specifically, it addresses the need for the cloud service provider (CSP) to provide assurance to the customer regarding the security of the underlying cloud infrastructure and services. This assurance is often delivered through mechanisms like audits, certifications, or contractual agreements that detail the security measures implemented by the CSP. The customer, in turn, remains responsible for securing their data and applications within the cloud environment, as well as for configuring the cloud services securely. Therefore, the most critical aspect for the customer to verify is the CSP’s adherence to security principles and their ability to demonstrate this adherence, which directly impacts the customer’s ability to meet their own regulatory and contractual obligations. This verification process is fundamental to establishing trust and ensuring that the shared responsibility model is effectively managed.

The core principle being tested here is the responsibility allocation for security controls in a cloud computing environment, specifically as delineated by ISO 27017. When a customer (user entity) utilizes a cloud service, certain security responsibilities are inherently transferred to the Cloud Service Provider (CSP). However, the customer retains ultimate accountability for the security of their data and the configuration of the services they consume. ISO 27017 emphasizes a shared responsibility model. In this context, the customer is responsible for managing access to their cloud-based information systems and the data stored within them. This includes implementing appropriate authentication mechanisms, authorization policies, and ensuring that only authorized personnel can access sensitive information. The CSP is responsible for the security *of* the cloud infrastructure (e.g., physical security of data centers, network security of the underlying infrastructure), but not the security *in* the cloud as it pertains to the customer’s specific data and application configurations. Therefore, the customer’s responsibility to manage access to their cloud-based information systems and data is a direct consequence of their continued ownership and control over their digital assets within the cloud. This aligns with the principle that while a service is outsourced, the fundamental security obligations related to the data itself remain with the entity that owns and processes that data.

The core principle of ISO 27017:2015, particularly concerning the responsibilities of cloud service customers and providers, is the clear delineation of security obligations. When a cloud service provider offers infrastructure as a service (IaaS), the provider is typically responsible for the security *of* the cloud (e.g., physical security of data centers, network infrastructure, hypervisor security). The customer, however, is responsible for security *in* the cloud, which encompasses everything deployed on top of the infrastructure, such as operating systems, applications, data, and user access management. This division is fundamental to managing risk effectively in a cloud environment. Without this clear separation, there would be ambiguity regarding who is accountable for specific security incidents, leading to potential gaps in protection and difficulties in incident response and remediation. Therefore, the most critical factor in establishing a secure cloud service relationship, as per ISO 27017, is the precise definition and agreement on these shared responsibilities, often documented in a cloud service agreement or contract. This ensures that both parties understand their roles and can implement appropriate controls to protect the information assets.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the cloud service provider (CSP), while others are transferred to or shared with the CSC. ISO 27017:2015, in Annex A, outlines controls applicable to both CSPs and CSCs. Control A.6.1.1, “Roles and responsibilities,” is fundamental. It mandates that the responsibilities of the CSP and CSC for information security are defined and documented. In the context of data deletion and disposal, the CSP is responsible for the secure deletion of data from the underlying infrastructure when the service is terminated or data is no longer required by the CSP. However, the CSC is responsible for ensuring that its data is properly managed throughout its lifecycle, including initiating the deletion process and verifying that their data has been removed from the cloud environment according to their policies and any contractual agreements. Therefore, the CSC’s obligation extends to the secure deletion of their data from the cloud service, which includes initiating the process and confirming its completion, rather than solely relying on the CSP’s general infrastructure disposal. The question probes the CSC’s proactive role in data lifecycle management within the cloud context.

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 and managing specific security controls is a shared one, delineated by the cloud service agreement (CSA) and the nature of the control itself. ISO 27017 emphasizes the importance of clearly defining these responsibilities. Control 5.1.1, “Cloud service agreements,” mandates that agreements between CSPs and CSCs should clearly define the responsibilities of both parties regarding information security. Control 6.3.1, “Information security in the cloud supply chain,” further elaborates on the need for agreements to cover the security responsibilities related to cloud services. Therefore, the most critical factor in determining which party is responsible for a specific security control during a migration is the explicit definition of responsibilities within the cloud service agreement, informed by the shared responsibility model inherent in cloud computing and the specific controls outlined in ISO 27017. This agreement should detail how controls are implemented, managed, and monitored, ensuring that no gaps exist in the security posture during the transition. The shared responsibility model dictates that while the CSP is responsible for the security *of* the cloud, the CSC is responsible for security *in* the cloud. However, the specifics of this division, especially for controls that bridge the infrastructure and the customer’s environment, must be explicitly documented.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are retained by the cloud service provider (CSP), while others are transferred to or shared with the CSC. ISO 27017:2015, in its guidance on responsibilities, emphasizes that the CSC is ultimately accountable for the security of their data and the configuration of the services they consume. This includes implementing appropriate access controls, data encryption, and security monitoring within their virtual environments. The scenario describes a data breach originating from an improperly configured virtual machine accessible via the internet. This configuration is a direct responsibility of the CSC, not the CSP, whose obligation is to provide a secure underlying infrastructure and services. Therefore, the CSC’s failure to implement adequate security measures on their deployed virtual machine, which led to the breach, constitutes a direct violation of their responsibilities under the shared responsibility model as guided by ISO 27017. The question asks for the primary area of responsibility that was compromised. The improper configuration of the virtual machine’s network access controls falls under the CSC’s domain for securing their deployed assets and data.

The core principle being tested here is the customer’s responsibility for data security within a cloud environment, specifically in relation to ISO 27017. The standard delineates responsibilities between the Cloud Service Provider (CSP) and the Cloud Service Customer (CSC). While the CSP is responsible for the security *of* the cloud infrastructure, the CSC is responsible for security *in* the cloud. This includes the data itself, access management, and the configuration of services. In the scenario described, the customer’s failure to implement appropriate access controls and data encryption for sensitive financial records directly contravenes their responsibilities as outlined by ISO 27017. The incident, where unauthorized access to this data occurred due to these deficiencies, highlights a direct breach of the customer’s security obligations. Therefore, the most accurate classification of the root cause, from the perspective of ISO 27017, is the customer’s insufficient implementation of security controls for data and access management. This aligns with the shared responsibility model inherent in cloud security and the specific guidance provided by the standard for protecting information assets. The other options, while potentially related to broader security concepts, do not pinpoint the specific failure in the context of the customer’s obligations under ISO 27017 as precisely. For instance, a CSP’s failure to provide adequate security features would be a different matter, as would a general lack of security awareness without a direct link to a control failure. The scenario clearly points to a gap in the customer’s own security posture.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes Infrastructure as a Service (IaaS), the cloud service provider (CSP) is responsible for the security *of* the cloud (e.g., physical security of data centers, hypervisor security, network infrastructure). The CSC, however, is responsible for security *in* the cloud, which includes securing the operating systems, applications, data, and user access within their deployed virtual machines and services. ISO 27017 reinforces this by providing controls that address both provider and customer responsibilities. In an IaaS model, the customer has the most control and therefore the most responsibility for the security of the deployed environment. This includes patching operating systems, configuring firewalls at the OS level, managing user identities and access within the virtual machines, and encrypting data. Therefore, the CSC’s responsibility for securing the operating system and its configurations is paramount in an IaaS scenario.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are inherently retained by the CSC, regardless of the cloud service model (IaaS, PaaS, SaaS). ISO 27017 emphasizes that the CSC is responsible for managing and securing data within the cloud environment, including aspects like access control to data, data classification, and ensuring the security of applications developed or deployed by the CSC. The cloud service provider (CSP) is responsible for the security *of* the cloud infrastructure. Therefore, if a data breach occurs due to misconfigured access controls on data stored in a cloud storage service, and this misconfiguration was implemented by the CSC’s administrators, the responsibility for the breach lies with the CSC. This aligns with the control objectives and guidance provided within ISO 27017, which mandates that CSCs must understand and manage their security responsibilities. The other options represent scenarios where the CSP would typically bear responsibility, such as a vulnerability in the underlying cloud infrastructure or a failure in the CSP’s physical security measures.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are inherently transferred to the cloud service provider (CSP). However, the CSC retains ultimate accountability for the security of their data and the configuration of their cloud environment. ISO 27017:2015, in its guidance on responsibilities, emphasizes that while the CSP secures the underlying infrastructure and the cloud service itself, the CSC is responsible for managing access controls to their data, securing their virtual machines, and ensuring the security of their applications deployed within the cloud. The scenario describes a data breach originating from an improperly configured virtual machine accessible via the internet. This configuration is a direct responsibility of the CSC, not the CSP, as the CSP provides the platform but not the specific internal security posture of the customer’s deployed services. Therefore, the CSC’s failure to implement adequate network security controls for their virtual machine, which led to the breach, constitutes a violation of their responsibilities under the shared responsibility model as outlined by ISO 27017. The question probes the understanding of where the boundary of responsibility lies for such an incident.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are inherently transferred to the Cloud Service Provider (CSP), while others remain with the CSC. ISO 27017, in Annex A, outlines controls applicable to both CSPs and CSCs. Control A.7.1.1, “Information security policy for cloud services,” mandates that the CSC establish its own information security policy that addresses cloud service usage. This policy must consider the responsibilities of the CSC as defined in the cloud service agreement and the specific security requirements of the data being processed. Therefore, the CSC is responsible for defining its security requirements and ensuring its internal policies align with the shared responsibilities outlined by the CSP and the standard. The CSP’s responsibility is to provide the secure infrastructure and services as per the agreement, but the CSC must define how it will use these services securely and what specific controls it will implement to protect its data, considering the shared model. This includes aspects like access management to cloud resources, data classification, and incident response procedures that are within the CSC’s purview. The other options represent responsibilities that are either primarily the CSP’s domain (e.g., physical security of data centers, network infrastructure security) or are too broad and do not specifically address the CSC’s direct policy-setting obligation for cloud usage.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, the responsibility for security is divided between the cloud service provider (CSP) and the CSC. ISO 27017 provides guidance on this division. Specifically, the CSC is responsible for the security *of* the cloud, meaning the configuration and management of the services they deploy within the cloud environment. This includes aspects like identity and access management for their users, data classification and protection, and the security of applications they develop and run. The CSP, conversely, is responsible for the security *in* the cloud, which encompasses the underlying infrastructure, physical security of data centers, and the security of the cloud platform itself. Therefore, when a CSC experiences a data breach originating from misconfigured access controls within their deployed virtual machines, the responsibility for addressing and mitigating this breach, as well as preventing recurrence, lies with the CSC, as it falls under their purview of managing their cloud environment. This aligns with the principles of Annex A.1.1.2 (Information security roles and responsibilities) and A.1.2.1 (Segregation of duties) as applied in a cloud context, emphasizing the CSC’s role in securing their own data and access.

The core of ISO 27017:2015 is to provide guidance on information security controls for cloud services, building upon ISO 27002. When considering the shared responsibility model in cloud computing, particularly for a customer using Infrastructure as a Service (IaaS), the customer retains responsibility for securing the operating system, applications, and data. The cloud service provider (CSP) is responsible for the security of the underlying infrastructure (e.g., physical security of data centers, network infrastructure, hypervisor). Therefore, a customer’s contractual agreement with the CSP must clearly delineate these responsibilities. Specifically, controls related to vulnerability management of the customer-managed operating system, access control to the virtual machines, and data encryption at rest and in transit for data stored within the IaaS environment fall under the customer’s purview. The CSP’s obligation would typically extend to ensuring the security of the physical infrastructure and the virtualization layer. This distinction is crucial for effective risk management and compliance.

The core principle being tested here is the shared responsibility model in cloud security, specifically as it pertains to ISO 27017. When a cloud service customer (CSC) utilizes a cloud service, certain security responsibilities are inherently transferred to the cloud service provider (CSP). However, the CSC retains ultimate accountability for the security of their data and the configuration of the services they consume. ISO 27017 provides guidance on how to manage these responsibilities. Specifically, it emphasizes that the CSC must ensure that the security controls implemented by the CSP are adequate for their specific needs and that they implement their own controls for aspects not covered by the CSP. This includes, but is not limited to, data classification, access management for their users, and the security of their applications deployed within the cloud. The scenario describes a situation where a data breach occurred due to misconfigured access controls within the customer’s virtual machine, which is a responsibility that typically falls under the CSC’s purview, even though the underlying infrastructure is managed by the CSP. Therefore, the CSC is accountable for ensuring their configurations are secure.