The Nokia 1100 has been programmable so it can be used for calling by using other people's numbers as well as receiving short messages. This ability is exploited by hackers to break into the bank.
In a country like Germany, banks typically send a mTAN (Mobile Transaction Authentication Number or message of authentication number) to the phone. This number is used as a password to enter the bank site. People who want to transfer money using this number. This mTAN number is usually only used once.
The bank breakers take advantage of Nokia 1110's ability to "hijack" other people's short messages to break into the bank. However, Nokia claimed not to know about this. Every cell phone, he said, already has a security mechanism can only use a certain SIM (Subscriber Identity Module) Card number. This security mechanism is separate from the phone.
Nokia adds, there is a service operator that can hide the SIM Card number or divert calls. Usually it is done using a proxy server, the server that hijacks the connection between the recipient and the sender.
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