BTCrack 1.1 - Final version (FPGA support)
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Introduction

BTCrack is the worlds first Bluetooth Pass phrase (PIN) bruteforce tool, BTCrack will bruteforce the Passkey and the Link key from captured pairing* exchanges.

To capture the pairing data it is necessary to have a Professional Bluetooth Analyzer : FTE (BPA 100, BPA 105, others), Merlin OR to know how to flash a CSR based consumer USB dongle with special firmware.

Example of an Attack scenario :
  • Attacker reconstructs BD_ADDR of both Master and Slave through passive (reconstructing through a preamble sniff, even when the device is in hidden mode) or active means (redfang)
  • Attacker changes his BD_ADDR to the one of the Slave device
  • Attacker asks to pair with the Master indicating it has no key, the Master will more then often trash the old pairing data and request a new link key from the genuine slave
  • Attacker now captures the key (pairing) exchange taking place between the two devices as the users try to re-establish a connection
  • Attacker exports data to CSV format and imports into BTCrack
  • Attacker can now compromise Master and Slave Bluetooth device through usage of the cracked Linkkey and is able to decrypt the data transmitted between the bluetooth devices

Why the PIN is not as important as the LINKKEY
  • An Attacker will focus on recovering the Linkkey and not the PIN, here's why :
  • The Link-key allows remote connections without the victim noticing
  • The Link-key allows and attacker to connect to devices in non-pairing mode and non discoverable mode
  • The Link-key allows decryption of the data
History :
  • Olly Whitehouse - 2003 -Presented theoretic weaknesses in the implementation of the Pairing exchange 
  • Shaked and Wool - 2005 - Present their logic to break pairing exchanges and implement it in Private
  • Thierry Zoller - 2006 First implmentation and public release of the Shaked and Wool logic, breaking the encryption and recovering the LINKKEY. 
  • Thierry Zoller / David Hulton  - 2007 - Worlds first FPGA based Implementation of the

Screenshots :


Speed Comparison :
  • P4 2Ghz - Dual Core 200.000 keys/sec
  • FPGA E12 @ 50Mhz 7.600.000 keys/sec
  • FPGA E12 @ 75Mhz 10.000.000 keys/sec
  • FPGA E14 30.000.000 keys/sec
Known issues :
[+] Frontline 6.0 mixes Master & Slave Addresses

Changes :
1.0 First release
1.1 Intermediate Release
  • E12 + E14 FPGA Support ( http://www.picocomputing.com)
  • Speed increase (+15%)
Downloads :






Heisec 2007 Scheunentor Bluetooth Zoller



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