BusKill is an open-source hardware and software project that designs computer kill cords to protect the confidentiality of the system's data from physical theft. The hardware designs are licensed CC BY-SA and the software is licensed GPLv3. BusKill cables are available commercially from the official website or through authorized distributors.
The name BusKill is an amalgamation of "Bus" from USB and "Kill" from kill cord.[4]
History
The original BusKill prototype from 2017The BusKill Kit in 2022
The first computer kill cord was built by Michael Altfield in 2017.[5][6]
The term "BusKill" was coined by Altfield in January 2020 when publishing the first BusKill build and udev usage instructions (Linux-only),[1][7][8] and it was ported by cyberkryption from Linux to Windows a couple weeks later.[9][10] The project's official website launched the following month.[11]
The first OS X version of the BusKill app was released in May 2020[12] by Steven Johnson.
A cross-platform rewrite of the software based on Kivy was released in August 2020 with support for Linux, OS X, and Windows.[13]
The BusKill cable is a kill cord that physically tethers a user to their computer with a USB cable.[18][19]
One end of the cable plugs into a computer. The other end of the cable is a carabiner that attaches to the user.[20]
In the middle of the cable is a magnetic breakaway coupler, to allow the cable to be safely separated at any angle without physically damaging the computer or the user.[21][22]
The BusKill project maintains a cross-platform GUI app that can either lock the screen or shutdown the computer when the cable's connection to the computer is severed and the app is in the "armed" state.[18][26][27]
Use
If the computer is separated from the user, then a magnetic breakaway in the cable causes a USB hotplug removal event to execute a trigger in the app.[28]
The trigger executed by the BusKill cable's removal can lock the screen, shutdown, or securely erase the LUKS header and master encryption keys within a few seconds of the cable's separation.[29][30][31]
^ abAltfield, Michael (2020-01-02). "Introducing BusKill: A Kill Cord for your Laptop". Michael Altfield’s Tech Blog. Retrieved 2022-07-02. This post will introduce a simple udev rule and ~$20 in USB hardware that effectively implements a kill cord Dead Man Switch to trigger your machine to self-destruct in the event that you're kicked out of the helm position.
^Helen Leigh (Jan 14, 2022). Teardown Session 17: OpSec and Privacy with Michael Altfield (Video Interview). Berlin, Germany: Crowd Supply. Event occurs at 12 minutes, 35 seconds. Retrieved 2022-07-02. I decided to build this for myself actually in 2017, and then I published the article in 2020.
