Wangiri Call Scam - Missed Call from International Number

This is what happened to me:

A missed call from Papua New-Guinea. Well... I don't know anybody there, so they shouldn't be calling me.

It doesn't take too much investigation to realize, IT'S A SCAM!

Example: Have you been getting unexpected overseas calls? from Australia
and How to identify and report Wangiri fraud to Vodafone from UK.

The Vodafone article says:

What’s Wangiri fraud?

It’s receiving missed calls from international numbers you don’t recognise on either a mobile or a fixed-line phone.
The fraudsters generating the missed calls hope that their expensive international numbers will be called back
so that they can profit.

Looks like that scam has been going on for years. The reason is obvious, it's way too easy! Making automated calls and hanging up when the other side starts ringing doesn't cost you anything. The seriously expensive number unsuspecting victims will call back will apparently play you some music while making you wait as long as you like. Every minute the criminals will get a slice of your money.

How is this possible? How can you change the number you're calling from? Well, easy! You can do it too: https://www.spooftel.com/
"SpoofTel offers you the ability to spoof caller ID and send SMS messages. You can change what someone sees on their call display when they receive a phone call to anything you like!"

Entire world is using ancient telecommunications protocol SS#7. If you're really interested, read The Wikipedia article about it. There are number of flaws in it, as it is entirely based on the assumption only non-criminals have access to global telecommunications network. It used to hold true at the time it was created, but after that. Not so much. And that unchangeable thingie we have to thank for this and multiple other scams and security flaws.