SCAM warning - calls to BT landline pretending to be BT / HMRC

[gosforth]

I have 6 month old Digital Voice landline, as part of FF900, which never get's used (apart my own test calls between my mobile phone and landline) up to now, is ex-directory, has BT Protect, and NEVER was published anywhere...

Out of the blue sky, this week starting ringing several times a day, at different times...

These calls pretending to be regular numbers from area codes (for example): 01213, 01473, 01908, 0208 and last from yesterday even international prefix +41 (Switzerland)...

I never picked them up, and placing them to blacklist manually, due I am sure, as there is no way to Skip company from Birmingham, Greengrocer from somewhere, etc., to call me and it's clearly spoofing of legitimate numbers to convince people to pick phone call, and go through BT CallProtect, which should normally block them straight away...

Friend of mine is at absolutely same situation:

and picked some calls, which at the end, just ending up with much more aggressive and often calls (of course!).

One was pretending to be BT, and "your internet will be suspended"  etc.etc. (somehow know scenario), second pretending to be HMRC, and "if You don't tell me, you will be arrested" (again, well know scenario)...

I do believe, as BT is able, on infrastructure level, to block any calls, which spoofing numbers. There should be ability to pick this kind of "spoofed" ID and simply not allows it to go through. If any legitimate caller will be blocked, that's shame, but it's better to block one call by mistake, then leave millions of customers to be vulnerable by these **bleep**, and can be easily rectified, to provide correct ID information.

On BT mobile, for now, I do not have any trouble. It surprised me, as landline is heavily targeted, not mobile (I have special number for "internet" and there I can wrote essay what I see, it's heavily bombarded by spam, scam calls, but never picked, but it's why I keep my private number private, and have special "public" number, which could be exposed). 

[gspearson]

The rogue system just dials all the numbers that could exist - it knows the number works only if you answer.  Check the  number before you answer - if you don't recognise it, don't answer.  I'm ex-directory, calls not offered, number not released and I still get these calls. The numbers you see are not real.  I don't think I've ever told HMRC my telephone number.  It is only a scam if you answer.

[pompey1898]

Hi @gosforth ,

I you run a seach there are numerous on the Forum about spoofed numbers.  Regrettably there is no way of blocking them other than to use a call barring phone.

[gosforth]

@pompey1898 I doubt as BT is unable to identify, by NICC standards, as "presentation number" or "network number" send to CLI is not valid.

As long, this not match, call should not be allowed to go through and eventually be blocked on CP infrastructure...

While on Digital Voice, i do expect greater security, and I am aware, how easily You can "spoof" number on for example Asterisks. But even like this, You will have "presentation number" which will not match expected records, and should be easily blocked, or, when customer report it as spam and it's discovered as it, make network not accept it...

It's somehow labour extensive, but, soon or later, will lead to decreasing attempts over this way. As long as these crooks know, as any random spoofed number will goes through, they will continue this way...

[gspearson]

@gosforth  a bit cryptic for most of us.

[pompey1898]

Hi @gspearson ,

Cryptic or not I did not understand it 😀.

[gosforth]

@gspearson @pompey1898 apologies....

More human explanation...

Asterisk - software for VOIP (Voice over IP) acting as switchboard.

You are able setup it to showing any number you wants, depends service provider you using (most of them will allow that).

Means, if I wish to be seen as, say 0208 xyzxyz, I simply will be seen like that, because BT will allow call like that going through, without blocking...

For "checks" where call originated is used so called "presentation number" which, generally don't need to be origin phone number, and at most cases it will be not. Any Call provider, including BT should be able to "check" where really call coming from. Say, it's similar like IP address and MAC address....

Regardless what I will setup to my phone (or software, for example Asterisk), it must have "presentation number" which clearly and uniquely identify source of call. This is handled over even if call is "hidden number" or "withdrawn". It is used on 999 or 101, which will see where call coming from, despite you try to hide it.

This "presentation number" in theory must match records for phone number, which is calling you... This information must be handled from original operator through network all the way to BT.

that means, if that not match = suspected spoofing and must be not going through... 

This not happening, e.g. BT don't check it, and will allows go through any call, doesn't matter if legitimate, or spoofed.

It's in theory really hard to do so, because exist operators, who simply not comply with regulations, and not really bother to stick with them. Hundreds of SIP (VoIP) operators simply don't do that... 

If BT will not allow their calls to be routed, they will...

But that's not a case, unfortunately....