A software engineer has designed a so-called USB “kill cable” that can be used as a dead man’s switch to turn off or erase information on your Linux laptop when your device is stolen from a table or knee in a public place such as parks, shopping centers, and internet cafes.
It is called BusKill and was designed by Michael Altfield, a software engineer and Linux system administrator in Orlando, Florida.
The idea is to connect one end of the BusKill cable to a Linux laptop and the other to a belt. When someone pulls a laptop from a laptop or table, the USB cable disconnects from the laptop and triggers the udev script, which performs a series of preset actions.
These actions can be simple, such as activating a screen saver or shutting down the device (forcing a thief to bypass the laptop’s authentication mechanism before accessing any data), but the script can also be configured to erase device information or delete certain folders (to prevent thieves from retrieving any sensitive data or accessing a secure business back end).
“When using laptops in public places, we try to increase OpSec usage, such as using a good VPN provider, 2FA, and password database autofill to prevent network or shoulder-based eavesdropping,” says Altfield. But even then, after you authenticate, there’s always a risk that someone will steal your laptop! “
So far, though, Altfield will not sell off-the-shelf BusKill data lines for the time being. Linux IT experts post instructions on their website on how each person builds their own BusKill data lines.
Basic components include a USB flash drive (which can be empty without storing any data on it), connecting the BusKill cable to a secure latch on the belt, a USB magnetic separation adapter, and an actual USB cable.
Prices range from $20 to $45, depending on the BusKill configuration required for the device and the robustness of its components.
In addition, Altfield lists two sample udev scripts. One locks the device by activating the screen saver, while the second turns off the laptop.
Users will need to build their own scripts to erase data or delete sensitive folders, as these scripts will depend on where and type of data they want to delete.