The actuator blocks
The actuators actually act on the world (these are the things that actually do things that can be perceived by humans as "the things the system does," such as triggering heating, moving, and so on). These are your servos, your motors, your power transistors, and so on.
From a penetration testing point of view, interacting with the actuators can help you with:
- Collecting data that allows you to understand how the system works. Sometimes the data itself can be interesting in a creative way to exfiltrate internal states from the system (think about the original iPod 4G firmware extraction by Nils "nilss" Schneider where he extracted the boot loader via a piezo bleeping – how cool is that?!).
- Some actuators have a feedback mechanism (for example, a linked position sensing system). These sensors' presence may not be self-evident when looking at the sensor-related chips and interfaces on the circuit board.
- Since the actuator...
