Cybersecurity for CPAs – Cybersecurity Weaknesses of CPA Firms and How Cybercriminals Exploit Them

CPA firms, particularly smaller ones, often have cybersecurity weaknesses that hackers can exploit. As mentioned in our last blog, a 2022 survey by CPA Practice Advisor found that only 40% of CPA firms had a comprehensive cybersecurity plan in place! The AICPA published an article stating, “Cybersecurity isn’t an option for CPAs – it’s a necessity.”  

In order to understand what cybersecurity protections a firm must employ, business owners must possess basic knowledge of the vulnerabilities cybercriminals exploit. Below are typical vulnerabilities and how they can be exploited: 

1. Weak Passwords 

  • Weakness: Employees may use simple, reused, or easily guessed passwords, or fail to change default credentials. 
  • Exploitation: 
  • Brute Force Attacks: Hackers use automated tools to guess passwords. 
  • Credential Stuffing: If passwords are reused across sites, hackers can exploit leaked credentials to access systems. 
  • Phishing: Tricks employees into revealing passwords. 

2. Lack of Multi-Factor Authentication (MFA) 

  • Weakness: Absence of MFA makes it easier for hackers to access systems with just a stolen or guessed password. 
  • Exploitation: 
  • Account Takeover: Hackers use stolen credentials to access email, tax software, or accounting systems. 
  • Data Breaches: Gaining access to client files stored in cloud-based systems. 

3. Outdated Software and Systems 

  • Weakness: Unpatched systems leave vulnerabilities open to exploitation. 
  • Exploitation: 
  • Exploiting Known Vulnerabilities: Hackers use exploits for unpatched software (e.g., ransomware, malware). 
  • Zero-Day Attacks: Target unpatched flaws before they’re widely known. 

4. Poor Email Security 

  • Weakness: Lack of email encryption and spam filters. 
  • Exploitation: 
  • Phishing Attacks: Hackers send fake emails to steal credentials or install malware. 
  • Business Email Compromise (BEC): Hackers impersonate the firm to trick clients into transferring money or sharing sensitive data. 

5. Inadequate Data Encryption 

  • Weakness: Sensitive data is not encrypted at rest or in transit. 
  • Exploitation: 
  • Data Interception: Hackers intercept unencrypted data over public or insecure networks. 
  • Data Theft: If devices or storage systems are breached, unencrypted data is easily accessible. 

6. Insufficient Employee Training 

  • Weakness: Employees are unaware of cybersecurity risks or best practices. 
  • Exploitation: 
  • Social Engineering: Hackers trick employees into sharing confidential information. 
  • Phishing Scams: Employees may click on malicious links or download infected files. 

7. Lack of Network Segmentation 

  • Weakness: All systems are on the same network without proper segmentation. 
  • Exploitation: 
  • Lateral Movement: Once inside, hackers can easily move across the network to access sensitive data. 
  • Privilege Escalation: Exploit poorly secured areas to access high-value systems. 

8. Poor Vendor Management 

  • Weakness: Third-party vendors with access to systems or data may have weaker security practices. 
  • Exploitation: 
  • Supply Chain Attacks: Hackers exploit vendor systems to gain access to the CPA firm’s data. 
  • Credential Sharing: Vendors might reuse credentials or share them insecurely. 

9. Lack of Incident Response Plans 

  • Weakness: No formal plan to detect, contain, and respond to cyber incidents. 
  • Exploitation: 
  • Extended Downtime: Hackers can prolong the attack due to slow response. 
  • Greater Damage: Firms may be unable to contain or mitigate the impact of breaches. 

10. Improper Data Disposal 

  • Weakness: Firms fail to securely dispose of outdated hardware, paper records, or digital files. 
  • Exploitation: 
  • Dumpster Diving: Hackers retrieve discarded physical records. 
  • Data Recovery: Recovering data from improperly wiped devices. 

11. Over-Reliance on Legacy Systems 

  • Weakness: Older systems lack modern security features and updates. 
  • Exploitation: 
  • Exploiting Insecure Architectures: Hackers target vulnerabilities specific to legacy systems. 

12. Weak Wi-Fi Security 

  • Weakness: Use of unsecured or poorly configured wireless networks. 
  • Exploitation: 
  • Wi-Fi Snooping: Hackers intercept traffic on unsecured networks. 
  • Unauthorized Access: Exploit weak Wi-Fi passwords to infiltrate the network. 

13. Insufficient Backup and Recovery Systems 

  • Weakness: No regular or secure backups. 
  • Exploitation: 
  • Ransomware Attacks: Encrypt systems and demand payment, knowing the firm has no way to recover data. 
  • Data Loss: Hackers delete or corrupt data without a fallback option. 

How do cybercriminals exploit these weaknesses? 

Hackers often use a combination of tactics: 

  1. Reconnaissance: Gather information about the firm through public records, social media, or phishing attempts. 
  1. Initial Access: Exploit weak passwords, phishing, or software vulnerabilities to gain entry. 
  1. Persistence: Install malware or backdoors to maintain long-term access. 
  1. Data Exfiltration: Steal sensitive data for resale, fraud, or ransom demands. 
  1. Lateral Movement: Move across systems to access high-value targets. 
  1. Extortion or Ransomware: Lock systems or threaten to release stolen data unless paid. 

Contact Structured Technology Solutions today to learn how your firm can mitigate these weaknesses.