[bjt2n3904]

The non-LE protocol has been pretty difficult to breach from the hacker-hobbyist level. The communication protocol is incredibly complex, and the hardware simply doesn't exist to interface well with it. A lot of BT2.0 (ie: non LE) "security" comes from the fact it's just darn hard to interface with it.

[lucb1e]

That sounds weird, given that it's in so many devices. It runs on a normal frequency and is implemented in billions of devices, how is it hard to interface with?

[IshKebab]

You probably need low-level access to crack the security. Your average Bluetooth dongle won't provide that.