Introducing BusKill: A Kill Cord for your Laptop

Bus Kill: A USB Kill Cord for your Laptop

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.

Rubber Ducky I <3 you; you make hack time lots of fun!

Let's consider a scenario: You're at a public location (let's say a cafe) while necessarily authenticated into some super important service (let's say online banking). But what if--after you've carefully authenticated--someone snatch-and-runs with your laptop?

Maybe you can call your bank to freeze your accounts before they've done significant financial harm. Maybe you can't.

Or maybe your laptop was connected to your work VPN. In less than 60 seconds and with the help of a rubber ducky, the thief could literally cause millions of dollars in damages to your organization.

Surely there must be some solution to trigger your computer to lock, shutdown, or self-destruct when it's physically separated from you! There is: I call it BusKill.


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New Thumb Drive Encryption Procedure

In this article, I'll describe a procedure for preparing a brand-new USB flash drive for use. First we'll securely erase all the data on the drive, then we'll encrypt the entire drive, and--finally--we'll check the drive for bad blocks.

Ah, remember the good-ole days of spinning disks? When your OS could tell your hard *disk* to shred a specific sector? Like it or not, those days are gone in the land of USB flash volumes.

There's a lot of great reads on the complications of securely erasing data on a USB thumb drive. Unfortunately, a lot of the techniques are not universal to all technologies or manufacturers. Consequently, my approach is more ignorant, straight-forward, and broad (at the risk of causing these cheap usb drives to fail sooner & the process taking longer):

First, I make sure never to write any unencrytped data to the disk Second, when I want to wipe the disk, I fill it entirely with random data

Below are the commands that I use to prepare a new usb drive for my use immediately after purchase. These commands are presented as a rough guide; they're mostly idempotent, but you probably want to copy & paste them
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