Most people are surprised that Caller ID isn’t verified in any real fashion. With the appropriate software or third-party service, a spammer, scammer, phisher, or abuser can set Caller ID to nearly any number that will then appear on your phone.
Or, at least, that was true until relatively recently, when a pair of systems referred to amusingly by their acronyms STIR and SHAKEN finally allowed carriers to use cryptographic means to track a phone call’s assigned number from its origin all the way to your phone. It requires a lot of moving pieces, as telecommunications firms all have to work together to let the verification chain occur, but the FCC has heavily promoted it.
