Audit and assurance policies and procedures are the foundation for a strong security posture in the cloud. They establish a framework for assessing controls, ensuring compliance with industry standards, and meeting business requirements. Regular review and updates are crucial to keep these policies current and effective.

Where did this come from?

This control comes from the CSA Cloud Controls Matrix v4.0.10, released on 2023-09-26. You can download the full matrix here. The CCM provides a comprehensive set of controls that are specifically designed for cloud computing environments. It maps to many other security frameworks like ISO 27001, NIST 800-53, PCI DSS, and more.

Who should care?

Several roles should pay close attention to this control:

• Chief Information Security Officers (CISOs) with responsibility for the overall security program
• Compliance managers with a need to ensure adherence to industry standards
• Internal auditors with a mandate to assess control effectiveness
• External auditors with requirements to attest to the organization's security posture

What is the risk?

Without well-defined and enforced audit and assurance policies, an organization faces several risks:

• Non-compliance with regulatory requirements, potentially leading to fines and reputational damage
• Weaknesses in security controls going undetected and unmitigated, increasing the likelihood of a breach
• Lack of confidence from customers and partners who expect a certain level of assurance

While audit and assurance alone can't prevent every adverse event, they are a critical tool for identifying and remediating issues before they lead to major incidents.

What's the care factor?

For most organizations operating in the cloud, audit and assurance should be a top priority. The stakes are high when it comes to protecting sensitive data and maintaining trust. Even a single compliance violation or security incident can have severe consequences. At the same time, over-auditing can be counterproductive, consuming resources that could be better spent elsewhere. The key is to find the right balance based on the organization's unique risk profile and compliance obligations.

When is it relevant?

Audit and assurance policies are always relevant for organizations using cloud services, regardless of size or industry. However, they become especially critical in certain situations:

• When an organization is subject to strict regulatory requirements (e.g., financial services, healthcare)
• When an organization handles large volumes of sensitive data
• When an organization relies heavily on the cloud for mission-critical operations
• When an organization has a history of security incidents or compliance issues

On the other hand, a small startup with a low risk profile and minimal compliance requirements might be able to get by with a more lightweight approach to audit and assurance.

What are the trade-offs?

Implementing robust audit and assurance policies does come with some costs and trade-offs:

• Time and effort required to develop policies, perform audits, and address findings
• Potential friction with development teams who may see audits as a hindrance to agility
• False positives that consume resources without providing real security value
• Opportunity cost of focusing on audit and assurance instead of other priorities

Organizations need to weigh these costs against the benefits of reduced risk and increased confidence in their security posture.

How to make it happen?

Implementing this control involves several key steps:

1. Develop a comprehensive set of audit and assurance policies and procedures, covering:
   • Roles and responsibilities
   • Audit planning and scheduling
   • Evidence collection and analysis
   • Reporting and communication
   • Follow-up and remediation
2. Ensure policies align with relevant industry standards (e.g., CCM, ISO 27001, NIST 800-53)
3. Obtain approval from senior leadership and communicate policies to all relevant stakeholders
4. Establish an internal audit function with appropriate independence and authority
5. Develop an annual audit plan based on risk assessment and compliance requirements
6. Conduct audits according to the plan, collecting sufficient evidence to support findings
7. Report audit results to management and work with teams to remediate issues
8. Monitor remediation progress and conduct follow-up audits as needed
9. Review and update policies and procedures at least annually to ensure they remain current

What are some gotchas?

There are a few potential pitfalls to watch out for when implementing this control:

• Inadequate resources or expertise in the internal audit function
• Resistance from development teams who may see audits as a burden
• Over-reliance on manual processes and spreadsheets for audit tracking
• Failure to customize policies to the organization's specific cloud environment and use cases
• Treating audits as a checkbox exercise rather than an opportunity for continuous improvement

Some specific permissions that may be required for auditing in AWS include:

• iam:GetAccountSummary for reviewing IAM users, roles, and policies
• config:DescribeConfigRules and config:GetComplianceDetailsByConfigRule for checking AWS Config rule compliance (link)
• trustedadvisor:DescribeCheckItems for accessing AWS Trusted Advisor checks (link)

What are the alternatives?

While there's no direct substitute for a comprehensive audit and assurance program, there are some complementary practices that can help strengthen an organization's security posture:

• Automated configuration management and policy enforcement using tools like AWS Config and AWS CloudFormation
• Continuous monitoring and alerting using services like AWS GuardDuty and Amazon CloudWatch
• Regular penetration testing and vulnerability scanning to identify weaknesses
• Security training and awareness programs to promote a culture of security

Explore further

For more information on audit and assurance in the cloud, check out these resources:

• AWS Security Audit Guidelines
• Cloud Security Alliance's Security Guidance for Critical Areas of Focus in Cloud Computing
• SANS Cloud Security Curriculum

This control also aligns closely with several CIS Controls, including:

• CIS Control 3: Data Protection
• CIS Control 13: Network Monitoring and Defense
• CIS Control 16: Application Software Security
• CIS Control 17: Incident Response and Management

By implementing a strong audit and assurance program in alignment with the CCM and other leading frameworks, organizations can take a major step forward in securing their cloud environments and building trust with their stakeholders.