Keyboard Sniffers to Steal Data
BBC News (10/21/08) 

Doctoral students Martin Vuagnoux and Sylvain Pasini from the Security and Cryptography Laboratory at the Swiss Ecole Polytechnique Federale de Lausanne (EPFL) were able to monitor what people type by analyzing the electromagnetic signals produced by every keystroke.

The EPFL students developed four attacks that will work on a variety of computer keyboards, leading them to declare that keyboards are not safe to transmit sensitive information. Vuagnoux and Pasini tested 11 keyboards that connected to a computer through either a USB or PS/2 socket, though the attacks also work on keyboards embedded in laptops. Each keyboard tested was vulnerable to at least one of the four attacks they developed, with one of the attacks being effective at a distance of 20 meters.

The students used a radio antenna to fully or partially recover keystrokes by detecting the electromagnetic radiation emitted when keys are pressed. The research builds on previous work by University of Cambridge computer scientist Markus Kuhn, who explored ways of using electromagnetic emanations to eavesdrop and steal useful information.