[citation][nom]jhansonxi[/nom]I've seen a USB storage device that emulates a keyboard and mouse that was designed to install malware on any system it is plugged into. If the system automatically activates any USB-connected keyboards andthe active user's account can create/edit/execute any program (including .bat, .cmd, .vbs, .sh) then it is vulnerable. On most systems it can take over in about 3 seconds. It can't easily get root on a Linux system but can install keyloggers or exploit known daemon security holes. On Windows it can respond to the security dialogs.[/citation]
Exactly, it's not that hard to hack a system if you actually get physical access, regardless of the OS. Especially if it's a device that you can convince the user they need to install additional software in order to get full use of the device.