THC claims it can listen to any call, use other accounts to make calls and access the victim's voice mail. Hackers have claimed that they have successfully re-engineered a standard consumer hardware available from Vodafone store to intercept calls and gain administrator access into other user accounts.
The Hacker's Choice (THC) said in a blogpost http://thcorg.blogspot.com/2011/07/vodafone-hacked-root-password-published.html that their engineers managed to reverse engineer Femto Cell into a full blown 3G/UMTC/WCDMA interception device.

A Femto Cell is a tiny home router which boosts the 3G Phone signal. It is available from the Vodafone Store to any customer for 160 GBP, said THC

THC said that engineers exploited a design flaw and got full control of the Vodafone UK network.

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