Black Hat: Researchers hack femtocells to grab voice, data and SMS traffic

Las Vegas: Researchers are calling on mobile operators worldwide to drop support for femtocell units following harrowing proof-of-concept demonstration.

Security firm iSEC Partners drew a packed house at the conference when it demonstrated a simple system which compromised aVerizon femtocell unit and then used the system to gather nearby mobile traffic.

The real-time demo included the capture of voice calls, a display of SMS messages sent by volunteers in the audience and even a video demonstrating an attack in which web data traffic could be pulled to harvest user credentials.

The stakes were only raised further as the demonstration progressed, with researchers using the hacked femtocell to collect unique device identifiers for mobile handsets. The collected data was then used to 'clone' a test handset, potentially allowing an attacker to eavesdrop on coversations and place calls from the account of the cloned system.

While US carrier Verizon has since patched the vulnerability in question and was said by the researchers to be very cooperative, iSec researcher Doug DePerry warned that the exploit method used in the attack could be modified in the future or other modes of entry could be found to take over other femtocell units.

Rather, iSec believes that in order to prevent these sort of attacks network operators need to drop support for femtocells altogether and implement their security protections at the network level rather than rely on the relatively weak security of embedded devices.

“Your phone will associate to a femtocell without your knowledge,” explained DePerry.

“This is not like Wi-Fi, you do not have a choice.”

The researcer noted that certain Android devices provide users with an icon to notify them when their handset is connected to a femtocell network, though other popular models such as the iPhone do not.

For users who are looking for protection against possible femtocell attacks, the company said it is developing a free application which will force a handset to go into airplane mode when a femtocell detection is detected. The researchers noted that the app is largly precautionary and not intended for novice users.