I have good news! The infamous SS7 networks used by mobile operators to interoperate, e.g.
when you’re roaming — which were built on trust, essentially devoid of security, and permitted rampant fraud, SMS hijacking, eavesdropping, password theft, etc. — are being replaced. Slowly. But I have bad news, too! Which is: the new systems still have gaping holes.
One such was described at the Def Con hacking convention today by Dr. Silke Holtmanns of Nokia Bell Labs. She gave a fascinating-to-geeks-like me summary of how the IPX network, which connected five Scandinavian phone systems in 1991, using the SS7 protocol suite secured entirely by mutual trust, has grown into a massive global “private internet” connecting more than 2,000 companies and other entities. It is this private network-of-networks that lets you fly to another country and use your phone there, among many other services.
The quote which stood out most starkly from her slides regarding IPX was this: “Security awareness only recently started (2014).” That’s … awfully late to start thinking about security for a massive semi-secret global network with indirect access to essentially every phones, connected car,