A new academic paper introduces SPECTER, a covert channel designed to exfiltrate data from air-gapped and network-segregated systems. The technique relies on host-side USB power control, with a transmitter encoding bits through power modulation. Because the target environment is physically or logically isolated from conventional networks, the channel presents an alternate path for data leakage.
The attack assumes an existing compromise: the transmitter must already have administrative privileges on the host. From that position, SPECTER manipulates USB power draw to encode information, presumably readable by a nearby receiver. The paper's abstract does not detail the receiver side, but the mechanism centers on the USB interface as a communication medium rather than a data transfer bus.
Air-gapped systems are often considered resistant to remote exfiltration, but this work highlights how local hardware interfaces can become covert leak channels once an attacker gains sufficient access. The research adds to a growing body of work on side channels in physically isolated environments.