The lengths crooks go to

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rb99

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#265751 9-Feb-2020 12:36

Maybe this is old news too you folks -

https://www.theguardian.com/money/2020/feb/08/bank-couple-lose-43000-but-cant-get-a-refund

but regardless of whether you sympathise or not with the (un)lucky victims - 'scammers were able to keep the line open during this process, using fake dialling tones, phones ringing in series, and even phone transfers'.

rb99

gzt

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#2415207 9-Feb-2020 16:02

The article says after initial contact the victims called the actual contact center and says the fraudsters were able to keep the line open and intercept this process and continued the fraud call. That's very sophisticated if strictly true. Seems more likely there was a psychological method rather than telco.

Is there any telco/sip service mechanism that prevents full user disconnect and actually allows this?

xpd

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#2415208 9-Feb-2020 16:10

Probably just convinced the victim they could call the other number while keeping the line open.

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loceff13

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#2415211 9-Feb-2020 16:13

They tell the person(victim) that they can dial the number while on the active call with the scammer(then the scammer does a 3 way call to a third party of their own to pretend to be the bank). At no point does the victim ever contact their own bank/the number on the back of their card.

elpenguino

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#2415286 9-Feb-2020 19:46

I have heard about this before. A UK reporter wrote a story about how he got scammed by a money card swap at an ATM followed by a phone call he received from the /help desk/.

He discovered that in the UK a phone call is not ended until both parties hang up. In his case, and perhaps this one, the scam works as follows.

The victim receives a call from the scammer and then the victim makes a phone call to what they think is the help desk but they are actually still connected to the scammers.

Since standard anti-scam advice is to not trust incoming calls, the victim feels they trust the outgoing call they make to the /help desk/ and reveal critical information.

I dont know if the UK phone system actually works that way but the article was in a major UK paper. This link backs it up.

https://www.nidirect.gov.uk/articles/phone-scams-and-cold-calls

Technofreak

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#2415353 10-Feb-2020 08:56

elpenguino:

I have heard about this before. A UK reporter wrote a story about how he got scammed by a money card swap at an ATM followed by a phone call he received from the /help desk/.

He discovered that in the UK a phone call is not ended until both parties hang up. In his case, and perhaps this one, the scam works as follows.

The victim receives a call from the scammer and then the victim makes a phone call to what they think is the help desk but they are actually still connected to the scammers.

Since standard anti-scam advice is to not trust incoming calls, the victim feels they trust the outgoing call they make to the /help desk/ and reveal critical information.

I dont know if the UK phone system actually works that way but the article was in a major UK paper. This link backs it up.

https://www.nidirect.gov.uk/articles/phone-scams-and-cold-calls

I'm not sure that statement about both party release is correct, because of all the problems it would create. There would be continual on going fault complaints where one party hadn't "hung up" thus preventing the other party from making calls.

I know for a fact it was never the case in New Zealand when we used British Post Office exchanges. I know both British Telecom (or whatever they're called now) and Spark/Chorus use completely different equipment now so things well may be different.

We used to be able to modify a number so that the called party could "hold" the call to allow tracing of nuisance calls but that's no longer necessary with the modern exchanges. Having said that I've never heard of the calling party being able to "hold' the call which is what this scam apparently relies upon.

Even if it were so, the victim would need to consciously make a three way call for this to happen, assuming that was possible on the type of telephone exchange being used for the call. Otherwise they would not be able to establish the second call.

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rb99

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#2415362 10-Feb-2020 09:12

Was just wondering if when they were told to call the number on the back of their bankcards, maybe they just told them to dial the number straight away (i.e. without actually disconnecting) and added in a few sound effects.

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elpenguino

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#2415364 10-Feb-2020 09:24

Technofreak:
elpenguino:

I dont know if the UK phone system actually works that way but the article was in a major UK paper. This link backs it up.

https://www.nidirect.gov.uk/articles/phone-scams-and-cold-calls

I'm not sure that statement about both party release is correct, because of all the problems it would create.

It seems unbelievable but if you read the information at the link it does appear that's the way the UK phone system works.

Other Google results agree, with advice such as 'use a different telephone".

Rikkitic

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#2415414 10-Feb-2020 09:45

I also have a vague recollection of the UK phone system working this way. I think I remember someone pointing it out to me when I lived there. But it was a long time ago.

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MurrayM

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#2415420 10-Feb-2020 09:59

I've had friends tell me that the UK phone system worked this way, but that was from the 70's and 80's, I don't know if it's still this way now.

MurrayM

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#2415475 10-Feb-2020 10:05

There's some information about this at security.stackexchange.com (bit too long to paste the full thing here but here's a short version):

Analog exchanges did not permit the called party to clear the line (hang up). My understanding of the original reason for this is that the calling party was paying the bill, and there was no effective signalling (pre digital exchanges) up the line (from called party to calling party) to terminate the billing. Remember on long distance calls these calls were patched through manually. This could be used (and relied on) by those receiving calls, e.g. to hang up and pick up the phone elsewhere. I believe this to be the case universally in original analog exchanges (i.e. in every country). This feature is called Called Subscriber Held (CSH).

When digital exchanges came in in the UK, some people had come to rely on being able to hang up and pick up the phone elsewhere, and BT (well, the GPO as it was then) maintained this feature. All modern exchanges have a configuration knob or two ("Called Party Clear" and "Called Party Clear Timeout") which determines whether, and after how long, the called party can clear the call. BT have in recent times set this knob to 3 minutes. This knob has been a feature of System X, System Y (aka Eriksson AXE10) and 21CN phone exchanges. BT use a much shorter timeout on POTS lines configured for analog PABXs. The called party can clear automatically on ISDN2 and ISDN30, and also on mobile and VoIP.