Once they accessed the database, known as the Home Location Register (HLR), the researchers are able to determine which mobile provider a given subscriber uses, and then combine that with the caller ID data, giving them a profile of the subscriber.
But no details are given about how they got in. But really, this isn't that much more scary then a phonebook.
Second
They can spoof someone's mobile number, dial that same number using this dialing technique, and in many cases a call to a handset from that handset's number that goes to voice mail will bypass the voice-mail authentication mechanism.
I know my company, verizon, still requires your password even if you call from your number.
Third
builds upon earlier work on geolocation of GSM handsets and exposes a number of fundamental weaknesses in the architecture of mobile providers' networks.
But no further info is given...
Looks like there really isn't much news here except that maybe t-mobile doesn't require a password for voicemail if you call from your home phone number.
Always look over your shoulder because everyone is watching and plotting against you.