A group known as The Hacker's Choice (THC) has come out with a report saying Vodafone's Sure Signal femtocells can be used to intercept voice calls and text messages.
The Sure Signal femtocells are base stations people can install in their houses if the mobile coverage in the area is weak.
"THC is now able to turn this femtocell into a full-blown 3G/[UMTS]/W-CDMA interception device," the group said in a blog post, with the femtocell having to be within 50 metres of a mobile phone for it to be used to listen to traffic.
A detailed account was given on the blog on how THC modified the femtocell, which could also be used for call fraud and accessing voicemail.
Vodafone issued a statement saying it had already released a patch for the vulnerability in Sure Signal in 2010.
"Overnight on July 12, a claim appeared that hackers had found security loopholes in Vodafone Sure Signal which could compromise the security of Vodafone's network. This is untrue: the Vodafone network has not been compromised," said the statement.
Vodafone said the issue was detected at the start of 2010, and a patch was issued a few weeks later automatically to all Sure Signal boxes.
"As a result, Vodafone Sure Signal customers do not need to take any action to secure their device," the statement added.
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