Circles reportedly takes advantage of Signaling System 7 (SS7) weaknesses, the protocol suite used to route phone calls, to both track the location of mobile devices and intercept voice calls and SMS messages. It can be connected to a telecommunications company’s infrastructure or purchased as a cloud service. Circles has reportedly been linked to the NSO Group.
|Mobile||T1449||Exploit SS7 to Redirect Phone Calls/SMS|
|Mobile||T1450||Exploit SS7 to Track Device Location|