Ovrdrive is a USB device that, at first glance, looks like an ordinary pendrive. However, it has a special security feature: it only activates and displays its content when you connect three times in quick succession. This device is aimed at journalists in repressive areas and security researchers, but may also be useful for other open source hardware and privacy enthusiasts.
The operation of Ovrdrive is based on two identical circuits connected to a ATtiny24A microcontroller which controls the quick connect functionality. When the flash is connected, the microcontroller powers up and the CHG1 node charges through D2, staying high for a while before slowly discharging through R1 and body resistance. Capacitors C3 and C14 remain charged during the rapid on/off cycle.
Despite its common appearance, Ovrdrive offers security through the darkness, although it is not intended to replace cryptographic encryption. Additionally, it has a circuit that can reverse the voltage supplied to the flash chip and heat it to over 100°C, which can serve as a catalyst for a “homemade self-destruct implant".
The device was created by Ryan Walker of Interrupt Labs, a company dedicated to creating open source hardware and software. All associated software and hardware files can be found in a GitHub repository. The project is currently being funded on Crowd Supply and has reached more than half of its goal of raising about $3500. The USB drive can be purchased for $69 now at Crowd Supply, with free shipping within the US and a $12 shipping fee for the rest of the world. Orders are expected to ship by August 5, 2024.
Ovrdrive specifications
As for the its technical specifications, we have the following:
- Microchip ATtiny24A Microcontroller
- Software Encryption (user defined)
- USB Type-A connector, v2.0
- SM3257ENT Controller
- 8GB capacity
- NAND flash memory type – MT29F64G08CBABAWP
- Self-destruct system
- Dimensions: 60x18x8.5 mm
More information - Funding page