Encryption and key management are critical components of securing data in the cloud. To ensure these systems remain effective and aligned with organizational needs, it's essential to have a well-defined change management process in place. This article explores the Encryption Change Management control from the Cloud Security Alliance Cloud Controls Matrix and provides guidance on implementing it effectively.

Where did this come from?

This control comes from the CSA Cloud Controls Matrix v4.0.10 - 2023-09-26. You can download the full matrix here. The CSA CCM provides a comprehensive set of security controls mapped to various compliance frameworks. It's an excellent resource for organizations looking to improve their cloud security posture. For more on encryption and key management, check out the AWS Key Management Service Documentation.

Who should care?

This control is relevant for:

• Cloud Security Architects designing encryption and key management solutions
• DevOps Engineers responsible for implementing and maintaining those solutions
• Compliance Officers ensuring adherence to relevant standards and regulations
• Business Owners with a vested interest in protecting sensitive data

What is the risk?

Poor change management around encryption and key management can lead to:

• Data breaches due to misconfigured or outdated encryption
• Compliance violations and associated fines/reputational damage
• Service outages or performance issues caused by unsuccessful changes
• Inability to decrypt data if keys are lost or mismanaged

While strong encryption and key management greatly reduce risk, those benefits can be undermined without proper change control. Likelihood and impact of an adverse event will depend on the nature of the data and systems involved.

What's the care factor?

For organizations dealing with sensitive, regulated, or mission-critical data, the care factor here should be high. Any missteps in managing encryption changes can have severe consequences. Even for lower-risk scenarios, having a structured approach is important for maintaining a consistent security posture over time. Don't neglect this control.

When is it relevant?

Encryption Change Management makes sense whenever you are:

• Deploying a new encryption or key management solution
• Updating encryption algorithms or key lengths
• Rotating, revoking, or destroying encryption keys
• Modifying access policies or permissions around key management

It's less relevant for static environments where encryption is not a major focus. However, given the broad shift to the cloud, this is increasingly rare.

What are the trade-offs?

Implementing robust change management does come with costs:

• Increased process overhead and potentially slower change velocity
• Additional tooling and automation needs
• Higher training and awareness requirements for staff
• Opportunity cost of focusing on change management vs. other priorities

However, these costs should be weighed against the risks of NOT having adequate controls in place. In most cases, investing in change management is well worth it.

How to make it happen?

1. Define your change management policy and procedures
   • Document the steps for proposing, reviewing, approving, implementing, and rolling back changes
   • Specify roles and responsibilities (e.g. who can approve changes)
   • Set criteria for classifying change risk/impact
2. Implement supporting tools and automation
   • Use version control and configure drift detection on key management infrastructure
   • Automate approval workflows and deployment pipelines where possible
   • Ensure ability to roll back changes if needed
3. Integrate with broader organizational change processes
   • Align with any existing enterprise change management frameworks
   • Ensure key stakeholders are looped in on major encryption/key management changes
4. Test and validate changes before implementing
   • Conduct thorough testing, especially for high-risk changes
   • Use separate development/staging environments
   • Incorporate security and compliance checks into validation
5. Communicate changes to relevant parties
   • Notify users and application owners of any planned service disruptions
   • Update documentation and runbooks
6. Monitor and audit
   • Check for unauthorized or out-of-band changes
   • Conduct security audits after significant changes
   • Track and remediate any issues found

What are some gotchas?

• Ensure you have the necessary IAM permissions to make changes to encryption and key management resources. For example, in AWS you will need kms:CreateKey, kms:ScheduleKeyDeletion and others depending on the change.
• Be aware of any upstream/downstream dependencies on encryption services. Changing encryption settings can break applications if not thoroughly tested.
• Remember that encryption keys have their own lifecycle. Factor key rotation and eventual deletion into your change management processes.
• Don't underestimate the communication needed, especially for customer-facing services. Encryption changes can be very sensitive.

What are the alternatives?

In some cases, you may be able to rely on cloud provider managed encryption services that abstract away some of the change management complexities. For example, AWS EBS default encryption or S3 default encryption can reduce the need for direct key management.

However, for maximum control and flexibility, implementing your own change management process is still recommended. This is especially true for organizations with stringent regulatory requirements.

Explore further

• NIST SP 800-57 Part 1 - Recommendation for Key Management
• CSA Key Management in the Cloud
• CIS Controls v8 - Control 3: Data Protection

Proper encryption change management is a critical but often overlooked aspect of cloud security. By following the guidance in this article, you can ensure that your encryption and key management systems stay robust and aligned with your organization's needs over time. Don't neglect this important control!

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