  Wireless charging is becoming an increasingly popular charging solution in
portable electronic products for a more convenient and safer charging
experience than conventional wired charging. However, our research identified
new vulnerabilities in wireless charging systems, making them susceptible to
intentional electromagnetic interference. These vulnerabilities facilitate a
set of novel attack vectors, enabling adversaries to manipulate the charger and
perform a series of attacks.
  In this paper, we propose VoltSchemer, a set of innovative attacks that grant
attackers control over commercial-off-the-shelf wireless chargers merely by
modulating the voltage from the power supply. These attacks represent the first
of its kind, exploiting voltage noises from the power supply to manipulate
wireless chargers without necessitating any malicious modifications to the
chargers themselves. The significant threats imposed by VoltSchemer are
substantiated by three practical attacks, where a charger can be manipulated
to: control voice assistants via inaudible voice commands, damage devices being
charged through overcharging or overheating, and bypass Qi-standard specified
foreign-object-detection mechanism to damage valuable items exposed to intense
magnetic fields.
  We demonstrate the effectiveness and practicality of the VoltSchemer attacks
with successful attacks on 9 top-selling COTS wireless chargers. Furthermore,
we discuss the security implications of our findings and suggest possible
countermeasures to mitigate potential threats.
