Serial PitM

This report explains practical methods for observing and performing person-in-the-middle on serial communications (UART/RS232) across two scenarios—an IoT authorization dongle and an industrial inverter—using crossover USB-serial setups, RS232 breakouts, and tools like `socat` for hex-logged relays; it further introduces a custom ESP32 + RS232 transceiver board with ESPHome firmware to enable low-latency snooping or active tampering, and discusses constraints such as baud-rate negotiation, hardware handshaking, and latency, with alternatives like USBProxy and Mallet.