The biggest issue for consumers is that there is little they can do to safeguard against this kind of snooping, short of turning off their mobile phone, as the attack happens on the network side, regardless of the phone used. Nohl pinpointed Lieu’s movements down to districts within Los Angeles, read his messages and recorded phone calls between Lieu and his staff.
He tracked a brand new phone given to US congressman Ted Lieu in California from his base in Berlin using only its phone number. Nohl, who is currently conducting vulnerability analysis of SS7 for several international mobile phone networks, demonstrated the hack for the CBS show. When calls or text messages are made across networks SS7 handles details such as number translation, SMS transfer, billing and other back-end duties that connect one network or caller to another.īy hacking into or otherwise gaining access to the SS7 system, an attacker can track a person’s location based on mobile phone mast triangulation, read their sent and received text messages, and log, record and listen into their phone calls, simply by using their phone number as an identifier. 7 (SS7), also known as C7 in the UK or CCSS7 in the US, which acts as a broker between mobile phone networks. The hack uses the network interchange service called Signalling System No.