How to Detect a Data Breach in Your Accounting Firm: A Comprehensive Guide

In today’s digital age, data breaches have become a significant concern, especially for accounting firms handling sensitive financial information. A breach can lead to severe financial losses, damage to reputation, and legal consequences. So, how can you tell if your accounting firm has experienced a data breach? 

This article will take you through the most common breaches, what to look for and more importantly what steps to take if you have been breached.


Signs of a Data Breach

Unusual Network Activity

One of the first indicators of a potential data breach is unusual network activity. This could include unexpected spikes in data transfer, unauthorized access attempts, or unfamiliar IP addresses accessing your network. If you are working with your cybersecurity provider these monitors will already be in place but keep an eye on where people are logging into systems, and at what times.  

Strange Pop-Ups and Redirects 

If your staff starts seeing strange pop-ups, or gets redirected to unfamiliar websites, it could be a sign that malware or spyware has infiltrated your systems. Your team should also be aware of being redirected to fake versions of legitimate sites, make sure to check the URL before inserting sensitive information.  

Unauthorized Changes 

Keep an eye out for unauthorized changes in your system settings or configurations. This could include changes to user permissions, altered files, or unapproved installations of software. This could be the sign of a criminal trying to give themself access to the systems. 

Unexpected Account Lockouts 

If employees experience unexpected account lockouts or if login credentials no longer work, it might be due to attackers trying to gain access or lock you out of your own systems. 

This may sound a bit scary when you think about what data they have access to if they get into your systems. But don’t worry, there is a set of clear steps you should follow if you do suspect you are breached.  


Immediate Steps to Take if a Breach is Suspected 

1. Contain the Breach

First, contain the breach to prevent further data loss. Disconnect affected systems from the network and isolate compromised accounts. If you aren’t sure how to do this, make sure to contact your cybersecurity provider 

2. Assess the Scope

Determine the extent of the breach. Identify which systems and data have been affected and how the breach occurred. Again, this is something your cybersecurity provider can do on your behalf.  

3. Notify Stakeholders

Inform relevant stakeholders, including clients, employees, and regulatory bodies, as required by law and your firm’s policies. In both Australia as well as the US you are legally required to report the breach to the government, failure to do so may result in expensive fines.  

4. Secure Evidence

Preserve all evidence of the breach. This will be crucial for forensic investigations and any legal actions that might follow. Again, this is something your cybersecurity provider can do on your behalf.  

5. Remediate and Recover

Fix vulnerabilities that allowed the breach, restore affected systems, and ensure backups are secure and up to date. Implement stronger security measures to prevent future incidents. 


Detecting a data breach early can significantly reduce the potential damage to your accounting firm. By being vigilant for signs of a breach, taking immediate action if one is suspected, and implementing strong preventive measures, you can protect your firm and the sensitive data you handle. Stay proactive, stay informed, and keep your systems secure.