This is an MITM attack (man in the middle). DO NOT RETRIEVE MESSAGE. When you answer or retrieve the message, they connect with your device and upload any info they want to their device. They are capable of listening in to any conversations and also retrieve any texts you send/receive.They're after your skype details with this number. IT IS NOT BT!!! Skype to Skype is encrypted. Skype to any other platform is not. PPI repayments texts and calls are exactly the same thing. DO NOT REPLY TO IT!!! As soon as you do, there are three people in the room.
If you make a call to a company number (0500) etc., any number where you are likely to make a purchase, your call will be intercepted by the MITM attacker who will impersonate the call-centre employee, even with pre-recorded background noise. 'Hello, my name is ----, how can I help you today'? Your name is the first thing to be asked, your postcode is the next. They now have a geographical location for their victim, and the trawling for information starts. If you give them your card numbers it's all over. Remember, they don't know who you're calling, they just go by the number's characteristics, so if they don't say the name of whatever company you're calling, hang up.
Sadly, the only way to rid yourself of this parasite is to change your number; the problem being that if you've replied/retrieved this message, they already have the contents to your address book, so as soon as you send your contacts your new number, you inadvertantly send the MITM attacker your number too. This is a really nasty and hugely underestimated scam. As difficult to shake as Malaria.
The main problem in preventing the MITM attacks, is the phone companies not wanting to share their encryption/delivery methods of their trade and therefore the MITM attackers have free reign over their customers, safe in the knowledge that the phone company isn't going to do a damned thing about it. Peace.
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