Cyber-security researchers have successfully accessed Android and iOS smartphones remotely via charging cables, swiping touch screens without actually touching them.
The smartphones they hacked from a distance were Samsung Galaxy S20 FE, Apple iPhone SE (2020) as well as devices from Huawei, LG, and Xiaomi.
Security researchers from Zhejiang University in China and the Technical University of Darmstadt, Germany demonstrated the first wired attack in those smartphones that creates ghost touches on capacitive touchscreens via charging cables, and can manipulate the victim devices with undesired consequences — allowing malicious Bluetooth connections, accepting files with viruses, etc.
“Our study calls for attention to a new threat vector against touch screens that only requires connecting to a malicious charging port, which could be a public charging station, and is effective across various power adapters and even USB data blockers,” the researchers said in a paper titled “WIGHT: Wired Ghost Touch Attack on Capacitive Touchscreens”.
Despite the fact that smartphones employ abundant noise reduction and voltage management techniques, they manage to inject carefully crafted signals that can induce ghost touches within a chosen range.
“The underlying principle is to inject common-mode noises over the power line to avoid being effectively filtered yet affect the touch measurement mechanism, and synchronise the malicious noise with the screen measurement scanning cycles to place the ghost touches at target locations,” they said.
They achieved three types of attacks: injection attacks that create ghost touches without users touching the screen, alteration attacks that change the detected legitimate touch position, and denial-of-service attacks that prevent the device from identifying legitimate touches.
“Our evaluation on 6 smartphones, 1 tablet, 2 standalone touchscreen panels, 6 power adapters, and 13 charging cables demonstrates the feasibility of all three type attacks,” the team wrote.
To achieve this, the team connected smartphones to a “malicious charging port” that works via Lightning, USB-A, USB-CF and Micro-charging cables.
The hack worked across several power adapters and USB data blockers failed to block the attack, they informed.