One of the key pieces to our digital identities, whether we like it or not, is our mobile phone number. You likely use it one way or another in a two-factor authentication login (you shouldn't). Thing is, as it's been demonstrated quite a few times, they can be easily hijacked in a few easy steps by malicious actors ringing up carriers' customer service representatives — many of whom are all too understanding in helping users out of what's supposedly a stressful situation. So, just how easy is it to steal someone's phone number on a prepaid network? Researchers at Princeton University say extremely so in a recently published whitepaper draft.