Backdooring a HID Reader
A while back, I bought a HID Prox Pro II on eBay for some long-forgotten experiment — likely this . Outside of being well documented and cheaply available , @shakataganai wrote a fantastic article about how to connect it to an Arduino, which makes it ideal for some testing. HID Prox Pro II While exploring the device, I was disappointed that the actual components of the device (except the antenna) were sealed under some type of resin coating. Despite the components being inaccessible, I noticed there was a lot of available space inside…Big enough to fit an entire Proxmark3 . So — theoretically, it may be possible to install a device inside this empty space that could capture tag data whenever someone swipes. Interior of HID reader Proxmark3 sitting inside Feedback from folks on Twitter noted the potential for interference between the two devices — which makes sense, if the HID card reader is emitting a signal to power a card, a second device in close proximity c...