What is an audit log?

An audit log is a detailed, chronological record of all changes to an operating system (OS), application or device, with the purpose of tracking system operations and use.

Modern IT systems are extremely complex and often require a significant amount of oversight. When performance begins to lag, errors manifest themselves or security or compliance issues arise. Knowing who has accessed the system and what actions they have taken may be essential.

Also called audit trails, audit logs provide this relevant information. Acting as a record of events within a computer system, an audit log allows auditors and IT personnel to trace user actions. This can provide vital insight into how the system is being used, where problems may be occurring and what security weaknesses might be present and exploitable. Additionally, regulatory compliance may require that audit logs be maintained for a specific length of time.

As with most other aspects of business, detailed records that are easily accessible by authorised individuals provide a number of clear advantages. And, for those organisations that work within industries governed by compliance frameworks, audit logs are more than simply beneficial; they're a standardised requirement.

Here, we take a closer look at some of the most-common advantages of maintaining audit trials:

Graphic outlining the advantages of keeping audit logs.

Providing compliance

Common regulatory frameworks—such as PCI DSS and HIPAA—require the use of audit logs to prove compliance. These function as official business records, giving auditors essential resources for inspecting and approving IT systems, and helping protect businesses from potential fines or other penalties.

Improving security

The key to effective IT security is reliable knowledge. Audit trails offer detailed records related to all activity within the IT system. This not only includes standard activity, but also any activity that may violate data-security practices, include unauthorised data access or even indicate a security breach by an outside threat actor. Correctly used, audit logs help IT professionals identify possible security vulnerabilities, identity and remediate data misuse, and respond quickly to emergent security events. And, given their official nature, these logs may also be used as evidence in court.

Gaining insight

Understanding how users are interacting with a system is the first step to improving those interactions. By tracking user activity, administrators and other authorised monitors gain valuable insight into issues related to performance, productivity, efficiency and more. At the same time, they can more quickly identify and resolve potentially problematic issues before they have a chance to spiral out of control.

Managing risk

Regulators, partners, vendors and even customers want to know that a business is secure before they invest their time or resources into it. A clear audit trail details what security measures the organisation is taking to ensure data privacy. Using audit logs as part of a risk-management framework may help demonstrate that a business is a low-risk opportunity.

Given the many benefits associated with maintaining reliable audit logs, it's no surprise that these digital records are often applied across a range of use cases. These include the following:


Businesses that require compliance certification must have complete digital records of how their systems function and are being accessed and used. An audit trail gives auditors the information they need to ensure that the organisation is operating within acceptable parameters and without any problematic anomalies.

Threat detection

Combined with real-time tracking systems, audit logs can help IT specialists recognise abnormal and/or illegal actions occurring within the system. Audit logs give threat detection the evidence and insight it needs to quickly identify potential security issues as they arise.


In the event that an organisation is involved in legal action as a result of its data or IT systems, audit logs may be used as forensic evidence. This can help a company prove that it was operating within established compliance guidelines, and they can also be used as evidence against those who may have been taking illegal action within the system.

SOC reporting

System and organisation controls (SOC) reports give companies the confidence to work with service providers, showing that they are operating in a compliant manner. Audit logs make SOC reporting easier and more complete, helping vendors clearly establish their credibility and trustworthiness.

Debugging and continuity

Audit logs allow businesses to place IT-system activities under a microscope. This makes it possible to quickly discover and resolve even low-impact bugs, and also simplifies recovery following a security intrusion.

To provide the above benefits, an audit log must include a number of essential details. These details help establish a clear picture of the IT environment and the circumstances associated with every action within the system. As such, a reliable audit log must include:

Terminal ID

A unique identifier associated with an individual terminal that can be used to identify the source of the system access.

User ID

A unique identifier associated with a specific user that can be used to identify who is accessing the system.

Date and time records

Reliable timestamps indicating when systems actions are being attempted or performed, as well as the overall time duration of system access.

Networks accessed

Information detailing which networks a user is attempting to access (even if the attempt is unsuccessful).

Access information

Information detailing which systems, data and applications a user is attempting to access.

Files accessed

Information detailing which specific files a user is attempting to access.

Changes made

Detailed information describing any changes made to the system, network, applications or files.

Utility usage

Details on which system utilities a user is accessing and how they are being used.

Security events

Information related to any security alarms or notifications that may be activated by the user.

System notifications

A clear record of all system notifications triggered by the user while in the system.

Thankfully, long gone are the days when access had to be manually logged and reviewed. Today, most relevant technology solutions include the automatic creation of audit trails, and the recording and storage of data for every action performed in the system, without exception. That said, there are still certain hurdles organisations may face when implementing a working log management strategy. These challenges may include the following:

Storage costs

Audits logs consist of large amounts of data, and the more processes, systems, devices and actions that are being tracked, the more storage space will be needed. This may create storage problems for businesses, increasing the necessary storage investment, either with regard to ensuring that your SaaS platform provider agreement includes ample data storage space, or if you haven't made the leap to a modern GRC solution, then setting up more in-house servers or paying more for off-site storage space.

Ineffective security

Although one of the primary advantages of an audit trail is that it allows for increased security, the audit log itself may represent a security vulnerability. When too many people have access to the audit log information, sensitive data captured during the audit may become exposed. One way to mitigate this is to establish persona-based landing pages and reports to view your audit activities and engagement tasks in real time. Likewise, audit logs themselves may be less secure than the systems they monitor, giving threat actors an easier path to sensitive data. Accessing them through a portal, from a secure SaaS platform, helps to mitigate this risk.

Record-keeping lengths

Even within a single organisation, disputes can arise over how long a digital record should be maintained. Some laws and regulations may establish a minimum duration (such as six months to seven years). Beyond that, it is up to the businesses to decide how long to store the audit log data before disposing of it. The further back the audit trail goes, the better protected the organisation will be, but keeping audit data for longer than is needed may represent an unnecessarily large amount of spend in terms of storage costs.

Difficulty balancing protection vs. performance

Overly thorough audit logs may slow down system responsiveness. Similarly to the previous point, IT decision-makers might have to work to find the right balance between security and system efficiency.

Too many log sources

Organisations that rely on a number of different systems, devices, applications etc. may encounter problems, as each log source produces its own audit log (or in some cases, produces multiple audit logs). This not only creates data-storage issues as mentioned above, but can also lead to inconsistent reporting, possibly making it difficult to link or reconcile audit trails across multiple sources.

Insufficient training or tools

Occasionally, log analysis may be treated as a low-priority task. As such, those who are responsible for carrying it out may not receive the right training or have access to effective tools. As a result, analyses may be rushed, incomplete, inaccurate or simply not be performed at all, except in response to a data breach or other emergent situation.

ServiceNow Governance, Risk and Compliance (GRC) brings audit management capabilities to a single, centralised location. Relevant data is automatically collected and analysed, audit trails are established and compliance and security issues are quickly identified. Learn more about Audit Management in ServiceNow GRC and get the insight you need to ensure that your systems and users are working together optimally.

ServiceNow makes the world work better for everyone. ServiceNow allows companies of all sizes to seamlessly embed risk management, compliance activities and intelligent automation into your digital business processes to continuously monitor and prioritise risk. ServiceNow Risk solutions help transform inefficient processes and data silos across your extended enterprise into an automated, integrated and actionable risk programme. You can improve risk-based decision-making and increase performance across your organisation and with vendors to manage the risk to your business in real time. And make risk-informed decisions in your daily work—without sacrificing budgets.

Get started with ServiceNow Governance, Risk, and Compliance

Manage risk and resilience in real time with ServiceNow.

Loading spinner