There is a new class of virii in town, specifically targeting Internet of Things (IoT) devices. BrickerBot and its variants do exactly as their name says, turning your smart devices into bricks. Someone out there has gotten tired of all the IoT security flaws and has undertaken extreme (and illegal) measures to fix the problem. Some of the early reports have come in from a security company called Radware, who isolated two variants of the virii in their honeypots.
In a nutshell, BrickerBot gains access to insecure Linux-based systems by using brute force. It tries to telnet in using common default root username/password pairs. Once inside it uses shell commands (often provided by BusyBox) to write random data to any mounted drives. It’s as easy as
dd if=/dev/urandom of=/dev/sda1
With the secondary storage wiped, the device is effectively useless. There is already a name for this: a Permanent Denial-of-Service (PDoS) attack.
Now any card carrying Hackaday reader will know that a system taken down like this can be recovered by re-flashing through USB, JTAG, SD, other methods. However, we’re not BrickerBot’s intended audience. We’ve all changed our devices default passwords, right? RIGHT?
For more IoT security, check out Elliot’s excellent article about botnets earlier this year, and its follow-up.