Audits provide a method to validate adherence to security policies and procedures by the business. Audits consist of verification and validation actions to identify compliance and non-compliance. The verification process in an audit checks the availability of suitable processes to support policies and procedures. The validation process in an audit to check adequacy, the correctness of a process, and the adequacy of controls.
When a business audits its processes through its internal audit department, then such an exercise is called an internal audit. An internal audit is generally performed by the business using its own resources. The purpose of an internal audit is to regularly validate various business systems for policy and procedural compliance.
In third-party audits, an independent agency or entity that is not associated with the business performs the audit. The auditors are external to the organization. The purpose of third-party audits is twofold. One is the independent verification of security posture. The other one is for certification purposes, such as compliance or standards-related certification.
In both internal and third-party audits, when the audits are performed on information systems, it is important to consider that such audits have a minimum disruption to business processes.
Some of the best practices in information system audit controls include the following: