Securing Information in Cloud Services: Best Practices and Strategies
The rapid adoption of cloud services has revolutionised organisational operations, offering unparalleled flexibility, scalability, and cost-efficiency. However, these advantages come with unique information security challenges that demand robust management.
ISO 27001 Control 5.23 requires organisations to implement structured processes for acquiring, managing, and exiting cloud services to protect their information assets and adhere to stringent security standards.
Contents
Purpose of Cloud Service Management
The primary objectives of managing cloud services include:
- Establishing and enforcing robust information security requirements.
- Clearly defining shared responsibilities between cloud service providers and customers.
- Mitigating risks related to data confidentiality, integrity, and availability in cloud environments.
Key Considerations for Managing Cloud Services
1. Define Clear Policies and Responsibilities
Develop and communicate a topic-specific policy on cloud service use. This policy should:
- Identify security requirements for cloud service deployment.
- Outline roles and responsibilities for cloud service management.
- Specify which security controls are managed by the cloud provider and which are handled by the organisation.
2. Conduct Comprehensive Risk Assessments
Risk assessments should be performed to evaluate vulnerabilities and threats linked to cloud services. These assessments must account for:
- The sensitivity and classification of organisational data.
- Jurisdictional regulations regarding data storage and processing.
- Residual risks, which should be reviewed and accepted by organisational leadership.
3. Establish Robust Cloud Service Agreements
Cloud service agreements should encompass the following elements:
- Specific requirements for data confidentiality, integrity, and availability.
- Defined service level objectives and qualitative performance measures.
- Backup, data recovery, and secure storage protocols.
- Incident management procedures, including digital evidence handling and resolution timelines.
- Provisions for secure exit strategies, ensuring data and configuration recovery during transitions.
Managing the Cloud Service Lifecycle
1. Selection and Acquisition
Establish criteria for selecting cloud services tailored to organisational needs. Ensure the chosen provider:
- Utilises industry-accepted architecture and infrastructure standards.
- Implements robust malware protection and monitoring mechanisms.
- Offers geographic and jurisdictional control over data storage locations.
2. Monitoring and Compliance
Implement a framework for continuous monitoring to ensure:
- Cloud service performance aligns with contractual obligations.
- Timely reporting and resolution of operational and security issues.
- Validation of the provider’s security measures through audits and certifications.
3. Managing Service Changes
Organisations should address changes to cloud services by requiring advance notifications for:
- Updates to technical infrastructure and service configurations.
- Relocations or changes in the jurisdictions governing data.
- Modifications to subcontracting arrangements or new supplier integrations.
4. Exit Strategies
Design and document secure exit strategies that minimise operational disruptions. These should include:
- Procedures for data retrieval, transfer, and secure deletion.
- Continuity measures for maintaining essential services during transitions.
- Management of backups, configurations, and other critical resources.
Best Practices for Secure Cloud Usage
- Shared Responsibility Model Clearly delineate the responsibilities of the cloud service provider and the organisation to avoid gaps in security coverage.
- Encryption and Access Controls Use strong encryption for data at rest and in transit, alongside robust access control measures to limit unauthorised access.
- Regular Security Assessments Conduct periodic evaluations of cloud services to identify and address vulnerabilities promptly.
- Incident Response Planning Develop and test incident response protocols to handle security events involving cloud services effectively.
- Collaborative Monitoring Maintain open communication channels with cloud providers to ensure mutual awareness and resolution of security issues.
FAQs
What is the objective of Control 5.23: Information Security for Use of Cloud Services?
This control ensures that information security risks related to the use of cloud services are identified and appropriately managed throughout the lifecycle of the service. The goal is to maintain the confidentiality, integrity, and availability of data hosted or processed in cloud environments.
What types of cloud services does this control cover?
It applies to all forms of cloud services, including:
– Infrastructure as a Service (IaaS) – e.g. AWS EC2, Azure Virtual Machines
– Platform as a Service (PaaS) – e.g. Google App Engine, Heroku
– Software as a Service (SaaS) – e.g. Microsoft 365, Salesforce, Dropbox
The control also applies whether the services are public, private, or hybrid cloud.
What are key information security risks with cloud services?
Common risks include:
– Loss of data control or unclear data ownership
– Insecure APIs or misconfigurations
– Third-party access to data (e.g. subcontractors)
– Data residency and compliance with legal jurisdictions
– Inadequate contract terms on security, privacy, or breach notification
What security measures should organisations apply when using cloud services?
To manage these risks, organisations should:
– Perform a supplier risk assessment before onboarding any cloud service
– Ensure clear contractual agreements on data protection, access, and breach handling
– Implement identity and access controls, including MFA
– Monitor usage through audit logs and alerts
– Use encryption, especially for sensitive data in transit and at rest
Who is responsible for ensuring cloud services are secure?
Responsibility is shared between the cloud service provider and the organisation (known as the shared responsibility model). While the provider manages infrastructure security, the customer is usually responsible for data security, user access, and configuration. IT, procurement, compliance, and data owners should work together to ensure coverage.
Conclusion
Effective cloud service management requires a strategic approach to information security.
By defining comprehensive policies, performing regular assessments, and fostering transparent relationships with cloud service providers, organisations can minimise risks while maximising the benefits of cloud technology.
These measures ensure secure and efficient cloud service usage, supporting operational objectives and safeguarding critical information assets.
