He Invented the USB Rubber Ducky to Fix Printers!

Summary

Darren Kitchen explains how the USB Rubber Ducky began as a practical IT automation tool and evolved into a security-testing device. While working in system administration, he wanted to automate repetitive tasks, such as repairing printers and reconnecting network shares. He initially put small circuit boards inside colored rubber ducks so coworkers could plug in the right one for a particular fix. The first USB Rubber Ducky was released around 2009.

How It Works

• The device can identify itself to a computer as a USB human interface device (HID)—in this case, a keyboard—rather than merely as a flash drive.
• It sends programmed keystrokes at high speed, reportedly over 9,000 characters per minute. A computer generally accepts those keystrokes as input from a keyboard, allowing the device to automate actions available to the logged-in user.
• Its capabilities depend on that user’s permissions and access; the device does not inherently grant elevated privileges.
• This behavior makes it useful for legitimate automation and authorized security testing, but also creates risks when someone plugs in an unknown device or trusts its appearance.

DuckyScript and Product Evolution

• The original DuckyScript was a small scripting language focused on sending keystrokes and adding delays.
• A later version expanded it into a fuller programming language, with features such as variables, conditionals, and loops. Kitchen describes it as useful for automation, security-awareness training, and authorized red-team work.
• The device can also support mass-storage functions. The interview discusses how an apparently ordinary USB device could be used to move data in ways permitted by the host’s access and environment.

Keystroke Reflection

Kitchen describes a technique he calls Keystroke Reflection. Keyboard indicator states such as Caps Lock, Num Lock, and Scroll Lock are communicated between a computer and connected keyboards. Because those signals may be shared across keyboards, a compatible device can observe changes and encode small amounts of information through them.

The interview presents this as a possible data-extraction channel, including in an air-gapped scenario, if the device is physically connected and the relevant system conditions allow it. It is suited to relatively small amounts of data, not large transfers. Kitchen notes that the keyboard LEDs may visibly flash during the process.

Other Points

• The conversation emphasizes the human-trust issue: people may mistake a device for an ordinary flash drive and plug it in.
• Kitchen discusses the history of keyboard input standards and how USB retained familiar keyboard behavior.
• He also mentions appearances of the Rubber Ducky in television and film, including Mr. Robot and Jason Bourne.
• A separate sponsor segment promotes Proton VPN and discusses IP-address privacy, location-based web content, and its NetShield feature.

Review or Tutorial

This is an explanatory interview and technical overview, not a product review or step-by-step tutorial.

Main Speakers

David Bombal (host) and Darren Kitchen (Hak5 founder and Rubber Ducky creator).