Swag as a Hidden Attack Vector, with David Hill

There was a pen on the table at a workshop. Placed next to an unlocked phone, it opened the browser and loaded the facilitator’s website, with nobody tapping anything and nobody agreeing to anything.

David Hill was in the room, at the back, and what he noticed first was the noise. When the facilitator stopped to explain why people had started talking, the reaction arrived in two parts: delight at a clever piece of marketing kit, then unease at what it had just done without being asked.

Recorded at AdelaideSEC, David joins David Savva-Willett to describe what happened next. He is an export adviser with the South Australian Department of State Development rather than a security practitioner, speaking here in a personal capacity, and he is open about how long he spent working out whether he was even entitled to take the pen apart, and what the right thing to do about it was.

Taking it apart revealed an NFC tag under the sleeve at the top. It also revealed that the tag had been left writable, so anyone who pocketed one could change where it pointed. He worked out how to do that from a search engine and a free app, with no prior experience of either.

The conversation covers why a workshop is precisely the room where your guard is lowest; why NFC has no equivalent of a Wi-Fi password, a Bluetooth PIN or the deliberate act of pointing a camera at a QR code; how cheaply programmable tags can be bought in bulk; and the finding he considers most important, which is that the phone most likely to react is the personal one nobody manages or trains anyone about.

He also describes how he raised it with the facilitator, in the first break, as an attendee asking about informed consent rather than an expert catching someone out.