Quote: "We can influence any pump within a 300ft [91m] range," Mr Jack told the BBC.
Most pump manufacturers have developed their own communication protocol. These protocols often just rely on obscurity instead of built-in security. In contrast the latest standard of bluetooth has established a high level of security. This has been tested and reviewed because it is an open standard that is based on key exchange. Thus I would consider the Accu-Chek Combo as being secure - although I do not know if they really use bluetooth 2.1
Here is another discussion:
https://forum.tudiabetes.org/topics/statement-from-animas-about-pump-hack