Security News > 2022 > June > Remotely Controlling Touchscreens

The core idea is to take advantage of the electromagnetic signals to execute basic touch events such as taps and swipes into targeted locations of the touchscreen with the goal of taking over remote control and manipulating the underlying device.

The attack, which works from a distance of up to 40mm, hinges on the fact that capacitive touchscreens are sensitive to EMI, leveraging it to inject electromagnetic signals into transparent electrodes that are built into the touchscreen so as to register them as touch events.

Abstract: Capacitive touchscreens have become the primary human-machine interface for personal devices such as smartphones and tablets.

In this paper, we present GhostTouch, the first active contactless attack against capacitive touchscreens.

GhostTouch uses electromagnetic interference to inject fake touch points into a touchscreen without the need to physically touch it.

By tuning the parameters of the electromagnetic signal and adjusting the antenna, we can inject two types of basic touch events, taps and swipes, into targeted locations of the touchscreen and control them to manipulate the underlying device.

News URL

https://www.schneier.com/blog/archives/2022/06/remotely-controlling-touchscreens.html