Dr. Shuo Wang and Team Devise ‘VoltSchemer’ Attacks Targeting Wireless Chargers

Dr. Shuo Wang

Wireless charging has become popular in recent years for portable electronics such as smartphones and smart watches due to its convenience. The existing wireless charging Qi standard has integrated measures to protect systems’ security. However in a recent paper, Dr. Shuo Wang and his team have disclosed hidden security and privacy vulnerabilities of smartphone wireless charging systems when they are under intentional electromagnetic interference (IEMI) attacks.

The paper, “VoltSchemer: Use Voltage Noise to Manipulate Your Wireless Charger,” has been accepted for USENIX Security ‘24.

VoltSchemer is an attack using voltage noise at the power supply to take full control of wireless chargers. The critical vulnerability enabling VoltSchemer is that changes in the input DC bus voltage can be converted to the voltage changes on the charger’s transmitter coil. Because the transmitter coil not only transmits power to the devices under charging but also transmits or receives data via in-band frequency or amplitude modulations, this effect has a straightforward impact not only on the power transmitted but also on the data exchanged with the device under charging. Exploiting this vulnerability, VoltSchemer can trick a charger into transferring power to metallic foreign objects, igniting or destroying nearby objects using extensively high temperatures. Besides, VoltSchemer can also manipulate a wireless charger to emanate an amplitude-modulated strong magnetic field, which can further inject inaudible voice commands into the voice assistant in a device under charging.

The research result has garnered significant attention from both industries and the media. The work has been widely reported by many media including: