Inaudible sound waves can transmit malware to unconnected computers.
With Christmas just 3 weeks away, the sound of the ludicrously high pitched Aled Jones’ “Walking in the Air” will undoubtedly be offending the eardrums of unsuspecting radio listeners any time now. Yet while the “The Snowman” had blissfully innocent overtones, scientists have developed Malware that could be walking through the air itself, with much more sinister intent.
Air gaps are used by computers in sensitive environments such as government institutions, nuclear power plants and air traffic control to stop data, such as keylogging, being transmitted to and from infected computers, simply by placing a physical void between computers.
Yet research by scientists in Germany has revealed that this technique is on the brink of becoming obsolete. The findings of the Fraunhofer Institute for Communication, Information Processing, and Ergonomics revealed that even basic laptops can communicate data through their internal speakers and microphones. While only small amounts of data can be transmitted (video and audio files are out of the question), the bandwidth available would still be sufficient to provide a trojan with a way of stealing passwords and personal data to social networks, online banks and email accounts.
The scientists ascertained that the data could “jump” as far as 19.7 metres (65 feet), which is worrying enough as it is, but also that a mesh network of hacker-controlled computers could theoretically carry data a great deal further. The sound waves are sent inaudibly, making it even more difficult for them to be recognised by potential victims.
The discovery that existing methods used to fight computer crime is simply part of the ongoing cat and mouse chase that defines computer security and the state-funded research into these dangers could potentially save embarrassing or dangerous slip ups in the future.