Massive, undetectable security flaw found in USB: It’s time to get your PS/2 keyboard out of the cupboardJuly 31, 2014 – 4:57 PM
Security researchers have found a fundamental flaw that could affect billions of USB devices. This flaw is so serious that, now that it has been revealed, you probably shouldn’t plug a USB device into your computer ever again. There are no known effective defenses against this variety of USB attack, though in the future (months or years, not days) some limited defenses might be possible. This vulnerability, which allows any USB device to take over your computer, mostly exists due to the USB Implementers Forum (the USB standards body) eschewing security in favor of maximizing the versatility, and thus the massively successful adoption, of USB. The USB IF itself notes that your only defense against this new attack vector is to only use USB devices that you 100% trust — but even then, as we’ll outline below, this won’t always protect you.
This flaw, dubbed BadUSB by Security Research Labs in Berlin, leverages the fact that every USB device has a controller chip. Whether it’s your PC, smartphone, external hard drive, or an audio breakout box, there’s a USB controller chip in every device that controls the USB connection to other devices. It turns out, according to SR Labs, that these controllers have firmware that can be reprogrammed to do a whole host of malicious things — and, perhaps most importantly, this reprogramming is almost impossible to detect.