What is an IT Security Audit?

The purpose of conducting an IT security audit is for an organisation to gain a level of assurance that implemented security controls and processes are achieving their intended outcome. Audits also provide an opportunity for organisations to proactively identify vulnerabilities that could result in a security incident.

To maximise the effectiveness of IT security audits, organisations should define a formal methodology to help ensure that such audits are performed in a consistent manner and a clear structure is followed.

Roles and responsibilities for both the auditor(s) and auditee(s) should be defined and communicated, and controls should be put in place to ensure that those responsible for leading the audit having sufficient knowledge, skills and experience in the various domains to be evaluated. Auditors should be impartial and provide an independent assessment of the organisation’s information security capabilities.

Why are IT Security Audits Important?

Organisations who perform regular IT security audits will benefit from an impartial and independent evaluation of their information security posture against an established framework or standard such as ISO 27001:2022. The in-depth examination of the effectiveness of implemented organisational, people, physical and technological controls also provides organisations with the ability to pre-emptively identify security gaps that cyber criminals could potentially exploit.

Where the findings of an IT security audit are positive, it helps IT leaders justify previous expenditure on new or enhanced security controls. On the flip side, audits that uncover several high impact security risks can be used to highlight where additional resources are required to mitigate against the impact and/or likelihood of such gaps materialising into something more serious.

Performing regular IT security audits helps embed good information security behaviours across key business processes. Success in audits cannot be achieved if controls are not maintained and managed all year round, so scheduling yearly audits helps promote improved accountability and responsibility when it comes to the effectiveness of implemented security controls. This in turn then promotes trust amongst interested parties that the organisation is actively taking their information security obligations seriously which can be evidenced through the audit reports and any subsequent certifications achieved, including the likes of ISO 27001 and SOC2 Type II.

How to Conduct an IT Security Audit

As mentioned above, IT security audits should follow a clearly defined methodology. Below is a summary of the key steps involved in the planning and execution of an IT security audit:

Confirm Audit Scope

The first step when planning an audit is to confirm the scope. This means determining which areas of the business and their underlying security controls are to be audited.  The audit scope may be a specific product or service, a particular region or group of regions, or it may be the whole organisation.

Create Audit Plan

Once the scope of the audit has been agreed with the key business stakeholders, the next step is to formulate the audit plan. This plan will form the basis of the audit and should include a detailed breakdown of what security controls are to be audited, when the various workshops will take place and which stakeholders should attend each session. It is imperative that the audit plan is signed off before moving any further in the process.

Documentation Review

A documentation review should be completed by the auditor(s) in advance of any interviews taking place. This will help the auditor build up a better understanding of the control environment within the organisation and helps them plan what questions need to be answered during the interview stage.

Interviews and Control Testing

Once the documentation review is complete, the next step is to complete all the interviews as per the agreed audit plan. These interviews can be conducted remotely, onsite or using a hybrid approach. During this phase, it is the responsibility of the auditee to demonstrate how effectively the in-scope controls have been implemented against the predefined audit criteria. The auditor will also perform any necessary technical checks at this stage which may include vulnerability scanning, configuration checks and log analysis. It is the responsibility of the auditee(s) to provide the required level of information to satisfy the requirements of the standard or framework the audit is being carried out against. Hiding information or not telling the truth will likely result in nonconformities been raised, so an open and honest approach is always recommended.

Report Writing & Debrief

Once all the interviews and technical checks are complete, the auditor will then draft their final audit report that should align with the reporting requirements set out in the audit methodology. There should be a clear breakdown of all findings including any nonconformities, observations and Opportunities for Improvement (OFIs) identified. Once the report is finalised, the last step is to conduct a debrief to ensure that all the findings are explained and understood.

IT Security Audit vs Compliance Audit

IT security audits and compliance audits are sometimes incorrectly mistaken for one another. Below is a summary of the key differences between these two types of audits:

IT Security Audit Challenges

Conducting IT security audits comes with various challenges that need to be navigated to ensure that the audit objectives are achieved. One of the key challenges is avoiding scope creep, where the boundaries of the audit expand beyond what was initially planned resulting in wasted resources and delays. Poor documentation of controls can also make it hard for auditors to evaluate how well security controls and processes have been implemented.

Other challenges that both auditors and auditees face include:

1. Prioritising remediation efforts, especially where there may be limited resources available.
2. Getting sufficient buy-in from those involved in control implementation who might adopt a defensive mindset and fail to provide the necessary information for the auditor to make an informed decision as to how well controls have been implemented.
3. The intention of the audit is incorrect. This sometimes happens in instances where organisations are performing the IT Security audit for the wrong reasons, such as pleasing a key customer or trying to increase their presence in the market.
4. The nature of audit means that they are a point in time assessment. As such, it can be difficult for auditors to have confidence that certain controls are working as intended over a longer period.

IT Security Audit Checklist

The IT security audit checklist will differ for each organisation depending on the nature of the services they provide and what the scope of the audit is. However, below is a summary of the typical domains often in scope:

• Governance
• Training and awareness
• Access controls
• Asset management
• Configuration management
• Vulnerability management
• Incident response
• Business continuity
• Network security
• Physical security
• Application security

For help in completing an IT Security audit, get in touch with one of our Cyber Security Audit Team.