NFC can be used to steal passwords over relatively long distances

[Father]

Checkmarx specialist Pedro Umbelino demonstrated a new method called NFCdrip, which allows small amounts of data (passwords or encryption keys) to be transmitted over relatively long distances using NFC technology.

The NFC protocol allows two devices to interact with each other at a distance of up to 10 cm. This technology, which is implemented in many modern smartphones, is used for payments, authentication or file exchange. As Umbelino found out, in reality, the technology is capable of working over longer distances and can be effectively used to covertly extract data from physically isolated devices with disabled Wi-Fi, Bluetooth or GSM.

The NFCdrip attack involves changing the NFC operating mode to modulate data. In the case of Android OS, you don't even need special permissions to change the mode, the researcher noted. NFCdrip uses on-off keying, one of the simplest forms of amplitude keying, where the presence of a signal is treated as 1 bit and the absence is considered 0 bits.

In the course of his experiments, the researcher demonstrated how malware installed on an Android device can be used to transmit a password to another Android gadget connected to a simple AM receiver, located at a distance of tens of meters. Data is transmitted without problems over a distance of 2.5 meters at a speed of 10-12 bits per second. Errors occur during transmission over a distance of 10 meters, but, according to Umbelino, they can be corrected. When transmitting over long distances, the signal weakens and a large number of errors occur, but the expert still managed to transmit some data over a distance of more than 60 meters. This value can be increased by using an AM antenna and SDR receiver.

According to the expert, the method can work on devices in "airplane mode" and poses a threat not only to Android devices, but also to laptops and other types.