Point-of-sale (POS) data breaches continue to be one of the most damaging and costly cybersecurity incidents in the retail, restaurant, and hospitality industries.
According to Verizon's 2025 Data Breach Investigations Report (DBIR), POS systems remain prime targets. The leading attack patterns: system intrusions, phishing/social engineering, and web application attacks, frequently compromise POS terminals, report support tools, and third-party vendor systems.
Here's how to identify the early warning signs of an attack and strengthen your defenses before it's too late.
What's Behind Most Point-of-Sale Attacks?
Modern POS breaches often stem from the same root causes that the industry faced a decade ago... they're just automated and more advanced now. Attackers frequently exploit:
- Default or reused credentials
- Weak or misconfigured remote access
- Unpatched operating systems and POS applications
- Malware injected through trusted vendor relationships
For organizations needing to reduce vulnerabilities and maintain PCI compliance, recognizing the early warning signs of an attack can prevent embarrassing, highly publicized security incidents.
6 Signs Your POS Security is Threatened
1. User Permission Changes
In many POS breaches that originate from weak or stolen user credentials, hackers must "elevate" permissions to navigate the POS network and push malware to terminals. Any sudden change in user access, particularly to administrative or super admin-level permissions, is a sign of unwelcome attention.
💡 Mitigation Tip: Continuously monitor permission and role changes using a system integrity monitoring tool to detect unauthorized privilege escalations in real-time.
2. Failed Login Attempts
A high number of failed login attempts can indicate that someone is attempting to brute-force their way into your POS system. Because many POS environments still rely on Windows-based remote management, RDP attacks remain one of the most common entry points. Any spike in failed login attempts, particularly during unusual times of the day or with unusual location metadata, should be taken as evidence of an ongoing attack.
💡 Mitigation Tip: Set thresholds for login failures and enable automated lockouts to stop brute-force attempts early.
3. Deviation from Normal Traffic Patterns
Monitoring baseline network activity is critical. While retail sales can be highly variable, depending on the time of day or season, understanding common traffic patterns in POS systems can be key to noticing deviations. By understanding what normal traffic patterns look like, your organization can detect when unusual spikes in traffic require deeper investigation.
💡 Mitigation Tip: Use network behavior analytics or SIEM integrations to alert on deviations from established baselines.
4. Unusual Connections
POS systems are typically composed of terminals, firewalls, payment processors, and remote support connections.
To gain access to sensitive cardholder data, hackers may attempt to enter from multiple points within the infrastructure; however, the remote support component is likely the most common and effective entry point.
Not only can unusual connections spell trouble, but strange activities between connected components of the POS infrastructure can also be a red flag. Outbound file transfers between your remote support and terminals can be signs of active malware.
💡 Mitigation Tip: Limit remote access to trusted networks, require MFA for all external connections, and monitor continuously for unauthorized activity.
5. Physical Tampering with POS Terminals
While modern POS attacks are digital, skimming and physical device tampering still occur. Attackers may install skimmers or swap out terminals entirely.
💡 Mitigation Tip: Inspect terminals regularly, log all maintenance or replacement activity, and train staff to recognize and report signs of tampering.
6. Unexplained or Sudden File Changes
Malware-originated POS attacks are highly effective for cybercriminals and crime collectives. After gaining entry to a third-party vendor or large retailer's network, they can push malware that conducts automated skimming out to all terminals, enabling the collection of millions of unique customer records.
Signs of a malware attack can include many of the components discussed above, such as failed log-on attacks or unusual traffic patterns. However, unusual file changes are equally common. With the help of sophisticated file integrity monitoring tools, security administrators may notice unplanned file changes on the remote host or the presence of new data files on the POS terminal after a malware infection is complete.
💡 Mitigation Tip: Use file integrity monitoring (FIM) to quickly identify and respond to unauthorized changes before they can spread.
Strengthening POS Security and PCI DSS v4.0 Compliance
Maintaining continuous PCI compliance isn't a one-time task. By actively monitoring your POS systems against PCI requirements and a healthy baseline, you can detect sudden changes in user activity, permissions, files, connections, and other signs of a breach in progress.
CimTrak offers coverage for a wide range of POS systems, including Windows XP, Windows Embedded for Point of Service, and POSReady. Our file system agent runs on your remote support, enabling administrators to detect attacks in real-time. When changes are detected, administrators have the ability to deny rights and reverse changes directly from the CimTrak management console.
To learn more about CimTrak's real-time change detection and monitoring for POS systems, download our PCI DSS v4.0 solution brief today.
