Designing Secure Hybrid Cloud Environments

09 Jan 2025

Security by design and not by chance when building a hybrid cloud environment.

Hybrid cloud environments provide flexibility, scalability, and cost efficiency by combining on-premises and cloud-based systems. However, these benefits come with significant security challenges. This post highlights some of the challenges and best practices for designing secure hybrid cloud environments, ensuring resilience and compliance with modern security standards.

Understanding Hybrid Cloud Security Challenges

Hybrid cloud environments blend on-premises infrastructure with public cloud service. Each platform presents different security requirements which introduces complexity when integrating both types together. Issues can be categorised into Data Breaches, Misconfigured Resources, Compliance Issues and Integration Complexity.

Data Breaches

Data breaches in hybrid cloud environments occur due to the complexity of transmitting and storing sensitive information across multiple systems and technologies. Key risks include:

Transmission Risks: Unencrypted data and the use of weak protocols (e.g., HTTP instead of HTTPS) can expose data to interception, such as via man-in-the-middle attacks.
Storage Risks: Misconfigured storage, shared infrastructure vulnerabilities, and inadequate encryption can leave data accessible to unauthorised users or at risk during media compromise.
Human Risks: Poorly managed access controls, exposed credentials, and insider threats (malicious or careless) further heighten the likelihood of data breaches.

Effective encryption, proper configuration, and strong access management are critical to mitigating these risks.

Misconfigured Resources

Misconfigured resources in hybrid cloud environments create critical security vulnerabilities that attackers can exploit to gain unauthorised access or escalate privileges. The complexity of managing configurations across on-premises and cloud environments heightens these risks. Key challenges include:

Lack of Unified Policies: Different security policies and tools across platforms can lead to inconsistent configurations.
Human Error: Manual setup increases the likelihood of mistakes, such as leaving ports open or mismanaging firewall rules.
Complexity in Hybrid Environments: Custom configurations required to integrate platforms can leave security gaps, as changes in one system are rarely reflected across others.
Rapid Scaling without Review: Scaling during migrations or workload spikes can bypass security best practices, creating overlooked vulnerabilities that remain unpatched.

These issues can be mitigated by standardising policies, automating configurations, and conducting regular security reviews.

Compliance Issues

Compliance issues in hybrid cloud environments stem from the need to adhere to legal, regulatory, and industry standards while managing data across on-premises, public, and private cloud systems. Key challenges include:

Data Residency and Sovereignty: Regulations such as GDPR require data to stay within specific regions. Hybrid clouds complicate tracking and controlling data storage locations.
Mixed Technologies: The use of diverse technologies from different vendors makes it difficult to ensure consistent security and privacy standards across all systems.
Inconsistent Policies: Different governance tools between platforms can lead to an inconsistent application of regulatory requirements.
Access Control and Monitoring: Regulatory access control and auditing requirements are harder to meet when various platforms provide different tools and capabilities.
Data Protection Standards: Applying consistent data protection measures (e.g., encryption, PII removal) across different platforms can result in non-compliance due to differing capabilities.
Third-Party Vendors: Cloud providers may act as data processors under some regulations. Ensuring they meet compliance standards is critical but often overlooked.
Audit Readiness: Maintaining audit readiness is challenging due to the mix of platforms and technologies, which require different tools and data collection methods.

To manage these challenges, organisations must carefully align technologies, policies, and tools to ensure compliance across all environments.

Integration Complexity

Integration complexity in hybrid cloud environments involves securing data flow and communication between diverse technologies, vendors and platforms. The key challenges include:

Diverse Systems and Technologies: Different platforms (e.g., AWS, Azure) use varied security protocols and tools, complicating secure integration.
Data Flow Security: Data moving across networks and cloud regions is at risk of interception, requiring encryption and secure communication protocols.
Authentication and Authorisation: Inconsistent identity management across environments can lead to weak access control and vulnerabilities.
API Security: Poorly secured APIs can become attack vectors, requiring robust authentication and monitoring.
Network Segmentation and Isolation: Improper network configurations may allow attackers to move laterally across systems.
Compliance and Regulatory Requirements: Ensuring compliance across different systems with regulations like GDPR and HIPAA can be challenging.
Monitoring and Visibility: Fragmented security monitoring across environments can hinder real-time threat detection and response.

To address these challenges, organisations must implement cohesive security policies, encryption, centralised identity management, and comprehensive monitoring.

Principles of Secure Hybrid Cloud Design

A strong foundation for hybrid cloud security begins with adopting key design principles. The following list summarises the key principles that should be aligned to in an architectural design.

Zero Trust Security Model: Assume no entity is trustworthy by default. Implement identity verification, least privilege access, and continuous monitoring.
Shared Responsibility Model: Recognise that security responsibilities are shared between your organisation and cloud providers. Clearly define boundaries to prevent gaps.
Scalability and Flexibility: Balance security needs with performance demands as your environment grows.
Compliance and Governance: Build systems that meet or exceed legal, regulatory, and industry standards. Automate compliance checks where possible.

Aligning to the above design principles when creating or updating a hybrid cloud environment can help to mitigate (or at least ensure you think about) many of the issues described above.

Best Practices for Securing Hybrid Cloud Environments

Securing hybrid cloud environments requires a multifaceted approach that combines various technologies, policies, and practices to protect both on-premises and cloud-based systems. Here are the best practices for securing hybrid cloud environments:

Implement Robust Identity and Access Management (IAM)

Implement robust IAM practices, including multi-factor authentication (MFA) and role-based access control (RBAC), to prevent unauthorised access. Some work is needed to ensure that there is either a single source for all user accounts, or if there are multiple sources, where they integrate to ensure there is no overlap or contamination if one is compromised. Where possible the creation, updating and decommissioning of user accounts should be automated and driven from a single system - such as a HR system to ensure that when a user changes role or leaves the organisation, their account(s) is(are) updated correctly.

Encrypt Data Everywhere

Protect sensitive data by encrypting it both at rest and in transit. This ensures data integrity and privacy, even in the event of a breach. The development of agreed policies and standards can ensure the same level of protection is provided, whichever technology is used. Properly manage encryption keys for data through a key management service and rotate keys regularly. Some Cloud providers provide the ability to enforce policies across all data storage resources (e.g. Azure Policy), however, the key here is to be consistent across platforms and technologies.

Establish Strong Network Security

Secure communication between on-premises and cloud systems using virtual private networks (VPNs) or software-defined wide area networks (SD-WANs). Network segmentation and advanced firewalls can limit exposure in the event of a breach while allowing the integration of platforms.

Monitor and Detect Threats Proactively

Use continuous real-time monitoring and Security Information and Event Management (SIEM) tools to detect and respond to threats proactively. Using a single SIEM tool with feeds from each platform can help to ensure a single view of the threat, particularly when combined with threat intelligence, even if there are multiple attacks to different parts of the environment. Automation can enhance response times and reduce human error.

Ensure Comprehensive Data Protection and Backup Strategies

Regularly back up critical data and develop both business continuity and disaster recovery plans. Ideally the disaster recovery plan should consist of automation and scripts that to enable a quicker recovery from any failure. DR systems should be tested frequently to ensure they work as intended during a crisis. Don’t forget about testing underlying services and look to identify single points of failure.

Ensure Compliance and Regulatory Alignment

Considering compliance regulations early on in the design of the environment can ensure that data is stored appropriately, including maintaining data within specific geographic regions where required. A complete and accurate audit trail of user activities, access requests, and data changes ensures accountability and supports forensic investigations in case of a security incident. Careful evaluation and monitoring third-party providers (including cloud vendors) ensure they meet the same security and compliance standards required by your organisation. Using automation tools to support the monitoring and reporting of compliance standards can simplify audits and ensure consistent adherence to regulatory requirements.

Implement a Strong Patch Management Strategy

All services, regardless of location or hosting platform should be automatically patched and updated on a regular basis. This includes operating systems, software applications, and security tools. Failure to patch vulnerabilities can leave systems exposed to exploits. Prior to deploying patches, you may wish to test them in a staging environment to ensure they won’t disrupt critical business applications or introduce new vulnerabilities.

Conclusion

Designing a secure hybrid cloud environment requires a proactive approach, blending robust architecture with vigilant practices. By addressing challenges, implementing core security principles, and adhering to best practices, organisations can create a resilient and compliant hybrid cloud.

It’s never too early to evaluate or update your security strategy—start today to ensure your hybrid cloud is prepared for tomorrow’s challenges.