With wireless internet, comfy seats and plenty of caffeine, coffee shops can seem like perfect places to work on some fresh content for your company blog.
But an afternoon of productive and satisfying blogging could be much riskier than you thought.
Most people will be aware of the threat of hackers exploiting the lax security of free wireless networks to get at your private information. But your laptop could still be “leaking” data even if it’s offline.
Researchers in the US discovered that side channel signals emitted by laptop computers, tablets and smartphones could be picked by various surveillance devices and used to capture passwords and other sensitive data.
In some cases, hackers would need to use sophisticated equipment such as a spectrum analyser, but in others these signals can be detected by a simple AM / FM radio.
“People are focused on security for the internet and on the wireless communication side, but we are concerned with what can be learned from your computer without it intentionally sending anything,” Alenka Zajic, an associate professor at Georgia Tech who worked on the research project, explained. “Even if you have the internet connection disabled, you are still emanating information that somebody could use to attack your computer or smartphone.”
Professor Zajic and his team noted a number of potential risks, including fake battery chargers that are in fact monitoring power fluctuations from your computer.
The aim of the study, which was sponsored by the National Science Foundation and the Air Force Office of Scientific Research, was to identify security loopholes so that they can be closed before hackers start to exploit them.
“We are measuring computers and smartphones to identify the parts of the devices that leak the most,” Professor Zajic said. “That information can guide efforts to redesign them, and on an architectural level, perhaps change the instructions in the software to change the device behaviour.”
The researchers did not find evidence from within the hacker community that these techniques are currently being used, but ironically their work provides some useful ideas for anyone keen to change that. It’s certainly enough to have you eyeing your fellow customers with suspicion the next time you need a proper flat white to inspire your writing.