Caller ID is not actually particularly reliable; it's about equivalent to the bottom "Received" line in an email message. That is, anyone who has a block rather than a collection of individual phone lines has the equipment which tells the system what the number is, and the rest of the system will believe it.
Posted Dec 18, 2008 18:30 UTC (Thu) by dlang (✭ supporter ✭, #313)
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it doesn't take someone with a block of phone lines. anyone with VoIP can also set their outbound callerID number.
I've also seen stories about it being possible to forge it from cell phones as well.
"Vishing" advisory targets Asterisk
Posted Dec 18, 2008 19:14 UTC (Thu) by iabervon (subscriber, #722)
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VoIP and cell phones are essentially access to somebody's block of phone lines, which may or may not allow you to do various things. What I was thinking of as "individual phone lines" are the single twisted-pair entering your house and going straight to your phones.