Your mobile number has quietly become the master key to your life. Banks text it codes, myGov sends it codes, and nearly every password reset ends with a message to your phone. So criminals have worked out that if they can take your number, by talking your telco into moving it to a new SIM or to another provider, they can get into almost everything else.

Photo: Donald Trung Quoc Don / Wikimedia Commons (CC BY-SA 4.0), resized