Altfield created BusKill looking for a cheap and “do it yourself” solution to cause the blocking, stopping or deleting computer data (with Linux operating system installed) in case someone physically separates him from the owner.
Basically, BusKill is a cable with a USB stick on one end. The ending in question connects to the laptop, while the other to the body of the laptop owner. When the USB stick is disconnected from the laptop, the action triggers a predefined command which can lock your computer, shut it down or erase the data.
Altfield spent about $ 20 to build BusKill, but the price may go up depending on the components used. A USB drive, a magnetic adapter, a carabiner and a USB extension are the elements behind BusKill.
You don’t have to save anything on the USB stick since its presence is only used to start the preset command; therefore it can be an economic key as long as the system recognizes it. The software part is instead tied to a script that starts only when a specific unit is removed. Below you can see a video showing BusKill in action:
BusKill comes in handy when working in a public space and accessing services with sensitive information, such as online banking or corporate VPN connection.
Altfield argues that although precautions such as two-factor authentication, a VPN or a password manager can be taken, there is still a risk that someone may steal the laptop after you authenticate.
BusKill is not available for sale, but Altfield provides all the details needed to create it. The project sparked a huge discussion on Reddit since the scenarios hypothesized by Altfield are by no means far-fetched and actually happen in real life.
The community has also developed other solutions to protect data on the notebook, so much so that Altfield is now thinking of writing a tutorial to expand BusKill’s capabilities and initiate a destructive deletion of content in the computer memory and in the LUKS (Linux Unified Key header) Setup) instead of the entire encrypted disk.
This approach would make the process faster and more effective because the LUKS header contains the symmetric keys required to decrypt the entire disk.