A hardware based firmware hack...a pretty nasty vector!
More detailed article hereDailyTech said:New Attack Compromises Apple Keyboards
Shane McGlaun (Blog) - August 3, 2009 10:05 AM
Attack infects keyboards to record keystrokes and more
No one wants to get their computer hacked or infected with viruses. For a long time, Windows PCs were the only real target of hackers and nefarious users, but as Apple Mac computers have become more popular hacks for these systems are now becoming more common.
A new hack that was demonstrated at DEFCON 2009 doesn't attack the software of Apple computers, rather it attacks the hardware.
Strangely it doesn't attack hardware inside the computer, rather the attack focuses on Apple's USB and Bluetooth keyboards. That means that once infected, the keyboard cant simply be repaired with a firmware update. The man who devised the hack goes by K. Chen and says he goes by that name because of fear that he would be harassed by Mac fans.
Once infected, the keyboard spits the text most recently typed in reverse order back onto the screen of the computer each time the enter key is pressed. The demonstration shows that the hardware attack is capable of recording keystrokes and injecting them back to the host machine. The key logging capability of the attack can also reportedly work during the boot phase unlocking more hardware and encryption features.
When the keyboard is infected, it can be used to run a bash connect back shell and then give the attacker full control over the computer allowing a root kit to be installed. The level of control is enough that the hacker could wait until the computer was idle and then start the attack.
The exact weakness in the Mac OS used to install the hack on the keyboard is unknown, but Chen says that the code needed to execute the attack in under 100kb and takes under 18 seconds to execute. Once infected the keyboard cant be fixed and would simply need to be replaced. Chen says he is working with Apple on a fix for the issue.
More and more security issues are being found with Mac computers as they grow in popularity and become more appealing targets for hackers.