Ryan Walker, known online as machinehum, built Phantomdrive: a fully open source USB flash drive with a hidden secondary filesystem encrypted with AES-256. The CH569 microcontroller handles decryption on-device, no software required on the host machine. The hidden partition is invisible to the operating system until unlocked.
The authentication method is the detail worth reading about. No keypad, no app. The drive's firmware monitors all write operations to the public partition and watches for the literal string 'password:' followed by the decryption key. Correct key, and the hidden volume mounts as a new drive. Wrong key, nothing appears. No visible indicator that a second partition exists at all.
Walker is explicit: this has not been professionally audited. Treat it as an experiment, not a hardened security tool. It follows his earlier self-destructing USB project from 2023, but without the pyrotechnics. The original post details the firmware architecture, the CH569 implementation, and the filesystem design. That is the part you should read.
[READ ORIGINAL →]