Malicious NFC tags: the dangers that smartphone users need to be aware of

While cash once dominated as a payment method, more consumers than ever are now using their mobile e-wallet as a contactless payment system for their purchases, replacing credit cards or e-tickets.

With smartphones increasingly relying on Near Field Communication (NFC) technology for convenience and connectivity, cybersecurity experts are warning of a growing threat, the breach of NFC tags. This tactic, which often goes unnoticed, can expose users to phishing attacks, malware and data theft through a simple contact with their phone.

"NFC technology is extremely practical, but it can be a vector for malicious activity if users are not careful," warns Marc Rivero, chief security researcher at Kaspersky. "Seemingly innocent tags in public places can be reprogrammed or replaced for harmful purposes. As the use of NFC expands into areas such as payments, public transport and marketing, we expect the malicious tactics of perpetrators to evolve further. In the coming years, thousands of users worldwide may be targeted by NFC-related attacks, particularly in urban areas where its use is widespread. Awareness and prevention measures are key to reducing these risks."

How the NFC tag breach works

NFC tags are widely used in advertising campaigns, public transport systems and smart home systems, offering fast and contactless interaction. However, it is precisely this convenience that makes them vulnerable to hacking by malicious users.

One of the methods they use involves reprogramming legitimate NFC tags. When left unlocked, these tags can be modified to redirect users to phishing sites, perform unintended actions on their devices or even spread malware. Another method is to physically replace the original NFC tags. For example, attackers may replace a genuine tag with a malicious one, for example on a public sign or in a booth in high-traffic areas such as transport hubs, cafes or shops.

The dangers of malicious NFC tags

The consequences of interacting with a malicious NFC tag can be severe. Among the most common consequences are phishing attacks, in which users are redirected to fake websites designed to steal personal or login information. By exploiting vulnerabilities in the mobile NFC reader sensor, attackers can execute malicious code and undermine the security of the device. Malicious NFC tags can also result in the download of apps or files containing malware, which can steal data, track activity or damage the device. The seemingly trivial act of scanning a compromised NFC tag can lead to significant financial and privacy implications.

How to protect yourself from NFC tag breaches

To stay safe, users are advised to adopt these simple but effective measures:

• Checking NFC tags. Avoid scanning in unreliable or suspicious locations and check for signs of tampering.
• Verify actions. Always carefully examine the URL or command triggered by a tag before proceeding.
• Disable automatic actions. Set your phone to require confirmation before it will execute NFC-related commands. Install a reliable security solution on the device to reduce risks.
• Continuous updates. Make sure your mobile software is up to date to protect against known vulnerabilities.
  Business tips

Organizations using NFC technology should take proactive measures to secure their systems and protect their users:

• Use NFC tags that are locked or "read-only" to prevent a breach.
• Check your tags regularly in public places for tampering.
• Educate your customers and employees on secure NFC practices.