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Calling on the official number is a good rule. But my neighbour followed that and was still scammed for tens of thousands. The critical extra step that they mi

by cjg 5y ago

Calling on the official number is a good rule. But my neighbour followed that and was still scammed for tens of thousands. The critical extra step that they missed was to check that the line was disconnected before calling out. They were using a landline. The scammers called them, but didn't hang up. Then, when my neighbour called out to their bank, they pretended to be answering that call - going through security, etc. My neighbour then did whatever the scammers said - because they couldn't possibly be scammers.

ghostly_s 5y ago
Your neighbor just dialed the new number without hanging up first?
- AdamTReineke 5y ago
  I could see this working if the other end played a click followed by and dial tone sound.
- harshreality 5y ago
  Unless both sides hang up, there's something like a 10-20 second window where the call is held open. Hanging up, picking up within 10 seconds and dialing, means you're still connected to the original caller. If they're clever, the might even detect the click of you hanging up, and play a dialtone for when you pick back up, and stop playing it when you start to dial.
  - ghostly_s 5y ago
    Citation needed. I don't recall any land line phone I've used behaving in this way.
- lostlogin 5y ago
  No dial tone and no ring… Seems a difficult mistake to make but then again, I regularly surprise myself with my errors.
  - bragr 5y ago
    There's nothing technical that prevents the other side from playing dial tone and ring sounds
e40 5y ago
The neighbor hung up, but the scammers didn't, and the call was not disconnected? That's not my experience. Is this what you meant?
- deleted 5y ago
  [deleted]
- afiori 5y ago
  Apparently it is a feature Called Subscriber Held (CSH). https://security.stackexchange.com/a/100342/143105 https://security.stackexchange.com/a/100342/143105 TL;DR It was just how analog phone worked, users came to rely on it, digital exchanges reimplemented it (with a timeout)
- BeefWellington 5y ago
  Yes, and this is how it works as another responder mentions. The thinking by phone companies is essentially: guy calling pays for the call, so we can milk each call for a few extra cents each time even if they're shady or a wrong number.
mdoms 5y ago
Your neighbour dialed a new number without hanging up his ongoing call? Is this his first time operating a telephone? The scammers mustn't have believed their luck when they realised that was happening. Did they mimic a "brnnnnggg brnnnggg" sound when he dialed?
- function_seven 5y ago
  The connection isn't always torn down immediately. Different switches behave differently in this regard. I remember a long time ago being trolled by a friend of mine who refused to hang up. I wanted to call someone else, but every time I picked up the handset to dial out, he was still on the line laughing at me. So if you're served by a switch that operates this way, the scammer just holds the line open, plays dialtone and ringback tones appropriately, and you're none the wiser.
- post-it 5y ago
  > Did they mimic a "brnnnnggg brnnnggg" sound when he dialed? Yes: https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone-scam-1.5375708 https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone... Looks like you would have fallen for it.
camtarn 5y ago
For the people who are confused: this is a fairly common thing on landlines in some countries, where the telephone exchange doesn't drop the connection until both ends have hung up, or in some cases when the caller hangs up but not the callee. So it's possible to put your own phone down, but when you pick it up again your phone is still connected to the scammer's telephone. If they play a convincing dial tone, then change to a ring tone when they hear DTMF, you'd be none the wiser. The workaround to this is to use another phone (e.g. switch to mobile), or if that's not possible, apparently you can wait several minutes until the exchange times out the connection. https://security.stackexchange.com/questions/100268/does-hanging-up-on-a-uk-landline-call-not-terminate-the-connection https://security.stackexchange.com/questions/100268/does-han...
- hunter2_ 5y ago
  It even makes the news [0] periodically. Watch the video, especially 2:22-2:36 which reiterates the PSTN behavior. [0] https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone-scam-1.5375708 https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone...
- afiori 5y ago
  I can confirm that at least once this happened to my family in Italy about 20 years ago. The most anecdotal statement ever, but a data point nonetheless.
- sometimeshuman 5y ago
  I accidentally won a radio contest many years ago in this way. I heard "you are caller 2" and then the DJ hung up. I stayed on because I was confused and then a few seconds later he picked up again and said you are "caller 4". So I just stayed on and eventually said I was caller 10 and the 10th caller won the prize. I assume he was switching back and forth between two internal phone lines. I was confused because I was calling to make a song request and had no idea that this contest was initiated because they had just played a certain song.
  - Spooky23 5y ago
mekoka 5y ago
So your neighbor hung up to proceed with a follow up call, which, if they're like most people, consists in just pressing the switch with a finger, while keeping the handset to their ear. But then upon releasing the switch, they just started dialing without waiting for the dial tone? And after they finished dialing and never heard the ringing tone, they didn't find that unusual? Forgive my skepticism, but something's missing from that story. Edit: Just read up on the disconnect time (10 seconds for some providers) and yes, a sophisticated scammer could indeed emulate the various tonalities.
- AdamN 5y ago
  scammer plays a dial tone after the 'hang up' and while dialing.
easytiger 5y ago
Was this in the UK? I think they dropped the timeout to help mitigate this. KNow someone else it happened to
megablast 5y ago
I guess we need to teach people how to use a phone line??

by cjg 5y ago

ghostly_s 5y ago

Your neighbor just dialed the new number without hanging up first?

AdamTReineke 5y ago
I could see this working if the other end played a click followed by and dial tone sound.
harshreality 5y ago
Unless both sides hang up, there's something like a 10-20 second window where the call is held open. Hanging up, picking up within 10 seconds and dialing, means you're still connected to the original caller. If they're clever, the might even detect the click of you hanging up, and play a dialtone for when you pick back up, and stop playing it when you start to dial.
- ghostly_s 5y ago
  Citation needed. I don't recall any land line phone I've used behaving in this way.
lostlogin 5y ago
No dial tone and no ring… Seems a difficult mistake to make but then again, I regularly surprise myself with my errors.
- bragr 5y ago
  There's nothing technical that prevents the other side from playing dial tone and ring sounds

e40 5y ago

The neighbor hung up, but the scammers didn't, and the call was not disconnected? That's not my experience. Is this what you meant?

deleted 5y ago
[deleted]
afiori 5y ago
Apparently it is a feature Called Subscriber Held (CSH). https://security.stackexchange.com/a/100342/143105 https://security.stackexchange.com/a/100342/143105 TL;DR It was just how analog phone worked, users came to rely on it, digital exchanges reimplemented it (with a timeout)
BeefWellington 5y ago
Yes, and this is how it works as another responder mentions. The thinking by phone companies is essentially: guy calling pays for the call, so we can milk each call for a few extra cents each time even if they're shady or a wrong number.

mdoms 5y ago

Your neighbour dialed a new number without hanging up his ongoing call? Is this his first time operating a telephone? The scammers mustn't have believed their luck when they realised that was happening. Did they mimic a "brnnnnggg brnnnggg" sound when he dialed?

function_seven 5y ago
The connection isn't always torn down immediately. Different switches behave differently in this regard. I remember a long time ago being trolled by a friend of mine who refused to hang up. I wanted to call someone else, but every time I picked up the handset to dial out, he was still on the line laughing at me. So if you're served by a switch that operates this way, the scammer just holds the line open, plays dialtone and ringback tones appropriately, and you're none the wiser.
post-it 5y ago
> Did they mimic a "brnnnnggg brnnnggg" sound when he dialed? Yes: https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone-scam-1.5375708 https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone... Looks like you would have fallen for it.

camtarn 5y ago

For the people who are confused: this is a fairly common thing on landlines in some countries, where the telephone exchange doesn't drop the connection until both ends have hung up, or in some cases when the caller hangs up but not the callee. So it's possible to put your own phone down, but when you pick it up again your phone is still connected to the scammer's telephone. If they play a convincing dial tone, then change to a ring tone when they hear DTMF, you'd be none the wiser. The workaround to this is to use another phone (e.g. switch to mobile), or if that's not possible, apparently you can wait several minutes until the exchange times out the connection. https://security.stackexchange.com/questions/100268/does-hanging-up-on-a-uk-landline-call-not-terminate-the-connection https://security.stackexchange.com/questions/100268/does-han...

hunter2_ 5y ago
It even makes the news [0] periodically. Watch the video, especially 2:22-2:36 which reiterates the PSTN behavior. [0] https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone-scam-1.5375708 https://bc.ctvnews.ca/beware-of-the-delayed-disconnect-phone...
afiori 5y ago
I can confirm that at least once this happened to my family in Italy about 20 years ago. The most anecdotal statement ever, but a data point nonetheless.
sometimeshuman 5y ago
I accidentally won a radio contest many years ago in this way. I heard "you are caller 2" and then the DJ hung up. I stayed on because I was confused and then a few seconds later he picked up again and said you are "caller 4". So I just stayed on and eventually said I was caller 10 and the 10th caller won the prize. I assume he was switching back and forth between two internal phone lines. I was confused because I was calling to make a song request and had no idea that this contest was initiated because they had just played a certain song.
- Spooky23 5y ago

mekoka 5y ago

So your neighbor hung up to proceed with a follow up call, which, if they're like most people, consists in just pressing the switch with a finger, while keeping the handset to their ear. But then upon releasing the switch, they just started dialing without waiting for the dial tone? And after they finished dialing and never heard the ringing tone, they didn't find that unusual? Forgive my skepticism, but something's missing from that story. Edit: Just read up on the disconnect time (10 seconds for some providers) and yes, a sophisticated scammer could indeed emulate the various tonalities.

AdamN 5y ago
scammer plays a dial tone after the 'hang up' and while dialing.

easytiger 5y ago

Was this in the UK? I think they dropped the timeout to help mitigate this. KNow someone else it happened to

megablast 5y ago

I guess we need to teach people how to use a phone line??