Understanding Cloud Security Audits: A Checklist for IT Professionals

As cloud environments become an integral part of corporate IT environments, they are increasingly targeted by cybercriminals. Cloud security audits assess an organization’s security controls to determine whether they meet industry standards. An auditor will collect information about existing security controls, test their effectiveness, and report on whether they meet regulatory requirements.

What is a Cloud Security Audit?

A cloud security audit is a formal assessment of an organization’s cloud security environment, designed to measure and improve its defenses against cloud security threats. Cloud security audits may be required for regulatory compliance or can be performed to enhance an organization’s security posture.

While compliance regulations commonly mandate annual audits, undergoing more frequent cloud audits can be beneficial for an organization. Some benefits of regular cloud security audits include:

  • Enhanced Security Posture: Cloud security audits identify vulnerabilities and misconfigurations in an organization’s cloud infrastructure, enabling it to address them before they can be exploited by an attacker.
  • Regulatory Compliance: Many regulations require regular audits of systems accessing sensitive, protected data. Even if an audit is not required, undergoing one can help identify compliance gaps and avoid regulatory penalties.
  • Customer Confidence: Regular security audits demonstrate that an organization is committed to protecting its customers’ data against cyber threats, building trust and credibility.
  • Cost Efficiency: The longer that a vulnerability persists, the more expensive it is to fix, especially if it is discovered due to a breach. Security audits can reduce security costs by proactively closing security gaps.

Comparing Audit Approaches: In-House vs. Third-Party

Depending on the purpose of the audit, an organization may have the option to perform an in-house audit or to engage a third-party auditor. Audits intended to bolster the organization’s security or to support regulations that allow self-certification can be performed in-house, while some laws require third-party audits.

Both approaches to audits have their pros and cons. Some advantages of third-party audits include:

  • Customer Trust: Third-party audits are generally considered the gold standard since the auditor is incentivized to provide an accurate report of findings. An internal audit may raise the question of whether any negative findings were accurately reported.
  • Blindspots: Sometimes, there is a significant difference between how things are supposed to be and how they really are. A third-party auditor performing a black-box assessment lacks the biases or blindspots that could cause internal users who are very familiar with the environment to miss security gaps.
  • Required Expertise: A cloud security audit requires in-depth knowledge of cloud infrastructure, cybersecurity, and regulatory requirements. With a third-party audit, one of the things an organization is purchasing is access to the expertise that they may lack in-house.

Internal audits have their advantages as well, including:

  • Comprehensiveness: An organization’s IT and security teams likely have more in-depth knowledge of their cloud environments than an auditor can achieve during an audit window. Internal audits can be an effective method of white-box security testing that takes advantage of institutional knowledge.
  • Cost: Third-party audits can be expensive because they involve hiring a skilled, certified auditor to perform an in-depth assessment of an organization’s cloud systems. Internal audits may be more cost-effective if the organization has the skills in-house to perform them efficiently and effectively.

At the end of the day, the decision of whether to use an internal or third-party audit boils down to three main factors, including:

  • Purpose: If an audit is for compliance with a standard that requires external audits, then a third-party audit is the only available option.
  • Stakeholders: In general, customers prefer to see third-party audits rather than internal ones. If the organization is performing an audit for its own purposes — improving security or preparing for a compliance audit — then an internal audit could be an option.
  • Capability: Auditing requires deep knowledge and expertise in multiple domains. If an organization lacks the required skill sets in-house, then a third-party audit is the best (and only) option.

Preparing for a Cloud Security Audit: A Step-by-Step Checklist

Preparation is key to a smooth, successful cloud security audit. Before beginning the audit process, take the following steps to prepare.

#1.  Define Audit Scope and Requirements

An audit that attempts to test every cloud system against every potential threat is doomed to fail. A manageable scope and clear objectives are essential to determining whether an audit was a success after the fact.

For compliance audits, the scope and requirements for the audit are usually defined by the regulation itself. For example, PCI DSS requires an audit of all systems that may have access to payment card data and includes a long list of requirements to test against. Non-compliance audits, on the other hand, should have a scope and requirements driven by business needs. For example, an organization concerned about account takeover attacks or insider threats might perform an audit of its cloud identity and access management (IAM) systems to ensure that they appropriately manage access to corporate cloud resources.

#2. Engage Stakeholders and Define Roles and Responsibilities

The results of a cloud audit can have consequences that reach throughout the organization. Without the right stakeholders on board, the audit process will take much longer or might miss critical information.

The team of stakeholders will depend on the scope of the audit and the roles and responsibilities assigned. However, members of the IT, security, and management teams should have visibility into any audit. Additionally, audits with an external customer should include legal representation.

#3. Select the Appropriate Audit Framework and Standards

For compliance audits, this step is already done for the organization. Regulations and standards have a framework and list of requirements that auditors are responsible for testing against. For self-directed audits, having a framework to follow guides the audit and helps to protect against oversight. The CIS Critical Security Controls and the NIST CSF are examples of well-regarded standards that include guidance for cloud security.

#4. Gather Necessary Documentation and Evidence

Security audits are based on a review of documentation and evidence. Once an organization has defined its audit scope and the standard that it will be audited against, it can collect the information necessary to prove compliance. This could include the existence of various processes, as well as evidence that certain security controls are implemented and that the organization hasn’t suffered a data breach.

Conducting a Thorough Cloud Security Audit

Some audit activities are performed by a third-party auditor, and some are the responsibility of the organization. Internal audit activities include:

  • Evaluating CSP Security Postures: Cloud service providers (CSPs) commonly undergo independent third-party audits under applicable regulations and standards, such as PCI DSS, SOC 2, and others. A cloud customer is responsible for requesting and reviewing the relevant reports for their service provider.
  • Testing Incident Management Plans: Many regulations and standards require organizations to have incident response (IR) and business continuity (BC) plans in place. The organization should perform regular tests of these plans, including walkthroughs, simulations, and red team exercises.
  • Compliance Management: Most companies are subject to multiple standards and regulations. The company is responsible for identifying relevant regulations and standards, implementing their requirements, and seeking out any mandated audits or security testing.

Other security audit responsibilities lie with the party performing the audit, whether the third-party auditor or the company in the case of an internal audit. Some important aspects of a cloud security audit include:

  • Security Control and Configuration Assessment: Security misconfigurations are a leading cause of cloud security breaches. Reviewing the security controls that a company has in place and its security configurations can help with identifying potential security gaps or regulatory non-compliance.
  • IAM Policy and Procedure Review: Weak IAM policies and procedures could lead to account takeover (ATO) attacks that result in unauthorized access to an organization’s cloud resources. The auditor should review the organization’s cloud IAM policies and procedures for adherence with regulatory requirements and security best practices.
  • Data Protection Review: Data protection is a common challenge in the cloud, with a significant percentage of sensitive cloud data being stored unencrypted. An auditor should assess the effectiveness of an organization’s cloud data protection mechanisms, such as encryption and backup strategies.

Auditing Multi-Cloud and Hybrid Cloud Environments

89% of companies have multi-cloud environments, and 73% have hybrid clouds. While these more complex cloud environments have their advantages, they also introduce additional security and auditing challenges, such as:

  • Security Visibility: Achieving required visibility in one cloud environment can be difficult due to the cloud-shared responsibility model. With hybrid and multi-cloud environments, this challenge is exacerbated by the need to monitor each platform and their interactions.
  • Consistent Security: Regulatory compliance requires implementing the mandated security controls across an organization’s entire IT infrastructure. Ensuring consistent security is more difficult with multiple cloud environments and their differing built-in configuration policies and security controls.
  • Configuration Management: Multi-cloud environments require the ability to properly configure security settings across multiple provider environments. This also increases the complexity of security audits since auditors need to verify settings on each platform.

A unified approach to cloud security management can dramatically simplify the process of achieving and auditing consistent security across multiple cloud environments. With one set of configuration settings that are applied to all environments, it’s easier to avoid security gaps and simpler for an auditor to verify an organization’s security configuration.

Interpreting Audit Findings and Prioritizing Remediation Efforts

The end result of a security audit should be a report detailing its findings, including security gaps that require remediation. After receiving the audit report, an organization should take the following steps:

  • Risk Scoring: An audit report should classify the audit findings as critical, high, medium, or low. If the organization performed the audit in-house or the report lacks this classification, the IT and security teams should review the findings and classify them accordingly.
  • Trend Identification: A security audit may identify several related issues, especially for hybrid and multi-cloud environments where the same issue may exist in multiple places. Identifying common issues can speed remediation and help with identifying and addressing root causes.
  • Remediation Planning: If an audit identifies security gaps or regulatory non-compliance, then remediation is necessary. The IT and security teams should develop a prioritized remediation plan and timeline, ensuring that the most critical issues are addressed first.
  • Stakeholder Communication: Throughout the remediation process, stakeholders should be kept informed of the audit’s results and the status of the remediation effort. This may be necessary to facilitate remediation in their areas of the business and helps demonstrate the value of the audit to the business.

After remediation is complete, an organization should re-audit affected systems. This verifies that the changes mitigate the identified vulnerabilities and haven’t introduced additional issues.

The Importance of Performing Regular Audits

Security audits provide various benefits for a business, including improved security, compliance, and customer confidence. However, an audit only evaluates security at a certain point in time. In a rapidly-changing cloud environment, the results of a security audit can quickly become outdated.

Performing regular audits is essential to maintain a strong security posture and customer confidence. Many regulations require annual audits — with quarterly vulnerability scans in the case of PCI DSS. However, more frequent audits are a good idea, especially for organizations with highly sensitive data or rapidly-changing cloud environments.

Audits should be performed at a regular cadence, after a security incident, and whenever a significant change has been made to an organization’s cloud environment and systems. Some best practices for ensuring successful, valuable audits include:

  • Measuring Success: Security audits should provide clear value to the business, both for themselves and the security solutions that they monitor. Tracking metrics such as the recurrence of particular security risks and the number of critical or high issues found and remediated can help to demonstrate business value.
  • Automate Security Testing: Manual audits are occasionally necessary but expensive in terms of time and personnel. Automating security testing — including building code analysis into automated DevOps pipelines — can provide useful security visibility and reduce vulnerabilities with minimal business impact.
  • Embrace Continuous Improvement: Regulatory audits are designed to ensure that an organization meets a minimum set of security standards, not that it will be secure against modern cyber threats. Proactively implementing and auditing additional security capabilities helps to reduce an organization’s exposure to cyber threats.

Simplifying Cloud Compliance with Cato Networks

Cloud security audits are important for cloud security, regulatory compliance, and customer trust. By undergoing regular audits, an organization can reduce its risk of cyberattacks and demonstrate that it has implemented appropriate security to protect its sensitive data.

Security audits require deep visibility into cloud infrastructure, which can be difficult to achieve with complex, multi-cloud infrastructures. Cato SASE Cloud simplifies cloud security and auditing by moving security to the network level, where it is consistent across platforms and providers. Learn more about how Cato can enhance your cloud security with built-in independent compliance and security assessments.