https://www.techdirt.com/articles/20180530/12054639943/another-report-highlights-how-wireless-ss7-flaw-is-putting-everyones-privacy-risk.shtml

Last year, hackers and security researchers highlighted long-standing vulnerabilities in Signaling System 7 (SS7, or Common Channel Signalling System 7 in the US), a series of protocols first built in 1975 to help connect phone carriers around the world. While the problem isn't new, a 2016 60 minutes report brought wider attention to the fact that the flaw can allow a hacker to track user location, dodge encryption, and even record private conversations. All while the intrusion looks like like ordinary carrier to carrier chatter among a sea of other, "privileged peering relationships."

Telecom lobbyists have routinely tried to downplay the flaw after carriers have failed to do enough to stop hackers from exploiting it. In Canada for example, the CBC recently noted how Bell and Rogers weren't even willing to talk about the flaw after the news outlet published an investigation showing how, using only the number of his mobile phone, it was possible to intercept the calls and movements of Quebec NDP MP Matthew Dubé.