IE 11 is not supported. For an optimal experience visit our site on another browser.

'USB condom' prevents device hijackings at rogue ports

The hardware blueprint for the device.Stephen A. Ridley

Worried about plugging your device into an unfamiliar port and exposing it to horrible viruses or trojans? Simply put this "USB condom" between the male and female ends before docking and the only thing transmitted will be safe, clean electricity.

Security-conscious individuals are probably aware that plugging your phone or drive into an unfamiliar computer or USB charging jack presents something of a risk. There are ways to hijack devices, surreptitiously install software or access files without the owner knowing. In less malicious, but potentially still awkward scenarios, the host computer may simply make an honest mistake and back up all your data — including pictures and financial information you weren't planning on sharing.

So if you're often charging on the go, and you don't truly know whether a given port is safe or not, it's time to think about a USB condom.

Another device manufactured by Ridley, the FaceDancer21, which also fiddles with the way USB interfaces work (the device was designed by Travis Goodspeed).Stephen A. Ridley

Every USB port and cable has several electrical channels, some of which are used to transfer power, the others data. The USB condom simply blocks the current on the data channels, meaning only the power channels make the connection between the device charging and the one being charged.

There are simpler solutions, such as power-only USB cables that simply don't have the data channels to begin with. But carrying two cables at all times could be a pain, and power-only cables may not come in the varieties you need — extra long, for example, or with a custom termination.

A USB condom may seem like overkill, but it may also be the easiest way to be sure your devices are safe from USB intrusion. The price is right, too: they should cost less than $10.

Unfortunately, the USB condoms, custom made by security and hardware specialist Stephen A. Ridley, are not available just yet — but he assures us that a shipment is coming on Sept. 16. And unlike Ridley's other, more experimental products, this one will come fully assembled.

Devin Coldewey is a contributing writer for NBC News Digital. His personal website is