In this work, we present a detection method
for adversarial electromagnetic interference
in sensor systems.
Sensor systems are used
when a microcontroller needs to interact
with the physical world.
A sensor transforms a physical quantity
into an analog signal
which is sent to a microcontroller
for digitization and further processing.
An attacker can manipulate the sensor output
by intentionally inducing
electromagnetic interference
in the wire between the sensor and the microcontroller;
the microcontroller cannot determine
whether the measurement is from the sensor
or the attacker.
If the microcontroller includes
incorrect measurements in its control decisions,
it could have disastrous consequences.
Our detection method is based on the idea that
if the sensor is turned off,
the signal read by the microcontroller should be 0V.
We use this idea to modulate the sensor output
in a way that is unpredictable to the adversary.
If the microcontroller detects
unexpected ﬂuctuations
in the sensor output,
the attacking signal is detected.
See the details in our paper
"Detection of Electromagnetic Interference
Attacks on Sensor Systems"
at S&P 2020.
