This time, the serious security flaw isn't in your phone's operating system, it's in the very system our phones use to communicate with each other around the world. A hacker who exploits this security bug would be able to hear all your voice calls AND see your exact GPS location.
The Australian TV program "60 Minutes" demonstrated how the hack works, and recorded an Australian senator's conversations and tracked his movements from Germany, thousands of miles away. The hack exploits a flaw in the global signaling system, called SS7, that makes roaming from one wireless carrier to another possible.
This hack is a "man-in-the-middle" attack, where the hacker forwards the call to an online recording device then back to the recipient. Besides intercepting calls and tracking people, this vulnerability could also intercept SMS verification used with banking apps.
This is a scary one, since the SS7 network is used worldwide. There isn't a fix yet, but governments are aware of the vulnerability in the SS7 network. Also, the hackers in Germany who intercepted the Australian senator's calls were given access to the SS7 network by the government, while hackers would have to break in.