Near-Field Communication (NFC)


Near-field communications (NFC) is a standard for two-way radio communications over very short (around four inches) distances.

  • is a peer-to-peer version of RFID
  • an NFC device can work as both tag and reader to exchange information with other NFC devices.
  • normally works at up to two inches (6 cm) at data rates of 106, 212, and 424 Kbps
  • NFC sensors and functionality are incorporated into smartphones
  • used for
    • contactless payment readers
    • security ID tags
    • shop shelf-edge labels for stock control
    • to configure other types of connections
      • e.g., pairing Bluetooth devices
    • “smart” posters
      • user can tap the tag on a poster to open a linked webpage via information coded in the tag
  • NFC transaction is sometimes known as a bump

NFC Wireless Connections

  • mobile devices have NFC chips built in
    • allows for very short-range data transmission to activate a receiver chip in the contactless reader
      • up to about 20 cm/8 in
    • data rates achievable are very low
  • On Android, NFC can be enabled or disabled via settings
  • device must be unlocked to initiate a transaction over a certain amount
  • can be used to configure other types of connection, such as pairing Bluetooth devices
    • E.g., if a smartphone and headset both support NFC, tapping the headset will automatically negotiate a Bluetooth connection

Wireless Mobile Payments

  • NFC allows a mobile device to make payments via contactless point-of-sale (PoS) machines
    • user enters their credit card information into a wallet app
    • wallet app does not transmit the original credit card information
    • a one-time token that is interpreted by the card merchant and linked back to the relevant customer account

Security

  • Attacks could be developed using vulnerabilities in handling the tag
  • possible to exploit NFC by crafting tags to direct the device browser to a malicious webpage
    • attacker could try to exploit vulnerabilities in the browser
  • NFC does not provide encryption
    • eavesdropping and on-path attacks are possible
      • if attacker can intercept the communication and the software services are not encrypting the data
  • vulnerable to several types of attacks
    • Certain antenna configurations may be able to pick up the RF signals emitted by NFC from several feet away
      • allow an attacker to eavesdrop from a further distance
    • attacker with a reader may also be able to skim information from an NFC device
    • attacker may also be able to corrupt data as it is being transferred through a method similar to a DoS attack
      • by flooding the area with an excess of RF signals to interrupt the transfer

Info

Skimming a credit or bank card will give the attacker the long card number and expiration date.

  • Completing fraudulent transactions directly via NFC is much more difficult
    • attacker would have to use a valid merchant account
    • and fraudulent transactions related to that account would be detected very quickly