Bitwhisper: Covert signaling channel between air-gapped computers using thermal manipulations

Mordechai Guri, Matan Monitz, Yisroel Mirski, Yuval Elovici

2015 IEEE 28th Computer Security Foundations Symposium, 276-289, 2015

It has been assumed that the physical separation (‘air-gap’) of computers provides a reliable level of security, such that should two adjacent computers become compromised, the covert exchange of data between them would be impossible. In this paper, we demonstrate BitWhisper, a method of bridging the air-gap between adjacent compromised computers by using their heat emissions and built-in thermal sensors to create a covert communication channel. Our method is unique in two respects: it supports bidirectional communication, and it requires no additional dedicated peripheral hardware. We provide experimental results based on the implementation of the Bit-Whisper prototype, and examine the channel’s properties and limitations. Our experiments included different layouts, with computers positioned at varying distances from one another, and several sensor types and CPU configurations (e.g., Virtual …