BLEKey is a Bluetooth Low Energy (BLE) enabled tap for the Wiegand protocol, which is the most widespread protocol for proximity card reader systems. BLEKey can be installed in a reader to passively sniff Wiegand data, and can emulate cards on that reader. All data can be offloaded to a phone with BLE support.
BLEKey is meant to be used by penetration testers and security practitioners to demonstrate the vulnerabilities in these access control systems. It can also be paired with a long range reader to create a card skimmer.
BLEKey requires a CR1632 battery (not included) to provide power.
All design files and source code are available on Github: https://github.com/linklayer/blekey
Whitepaper from Blackhat USA 2015 talk: https://www.blackhat.com/docs/us-15/materials/us-15-Evenchick-Breaking-Access-Controls-With-BLEKey-wp.pdf
Blackhat USA 2015 Talk: https://www.youtube.com/watch?v=seKas8KFcSI