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> Most phone providers are part of a scheme that allows customers to report suspicious text messages for free by forwarding it to 7726. If you forward a text to

by mdp2021 2y ago

> Most phone providers are part of a scheme that allows customers to report suspicious text messages for free by forwarding it to 7726. If you forward a text to 7726, your provider can investigate the origin of the text and arrange to block or ban the sender, if it’s found to be malicious It would be useful to have a list of Countries/operators adopting the 7726 ("SPAM") number. It seems also some European Countries do.

slowmotiony 2y ago
How do you forward a text?
- orra 2y ago
  Often there's a long click menu in your SMS app to do it. But all that really does is copy the body into a new SMS. There's no metadata to indicate it's forwarded, as you suspect. This means texting 7726 is a two step process. First you send the body. You immediately get a response asking for the phone number of the spam sender, so then you sent that.
  - lxgr 2y ago
    Does the phone number even matter for tracing? As far as I understand SMS delivery, it’s not authenticated at all. I suppose it can be used to help the operator identify the actual incoming message in their logs?
    - toast0 2y ago
      Source number authorization depends on how the messages get to the carrier and how the carrier has things setup. At the end of the day, there's a lot of trust though; and a lot of connections would be difficult/expensive to confirm that the connection is authorized to send messages from the sources they're using. Think of BCP38 for IP spoofing, but for number spoofing. If you get an appropriate country mobile number from a carrier in that country, are you going to pay for a portability lookup to confirm that carrier is the authorized carrier for that number? Does that carrier check source numbers for all of the connections they have? Some of the aggregators are good at checking sources, and some aren't, but aggregators are often authorized to send messages from many different countries, so they're likely to have their connections unchecked, because keeping the list updated is hard. It's like IP transit, but a lot worse.
doophus 2y ago
Would this even work in the article's situation, where someone's MITMing SMS?
- mdp2021 2y ago
  If you believe the cell you are under is compromised, further action should be performed under a different cell. Actually, I would like to have an option to identify the cells devices are connected to.
  - mminer237 2y ago
    CellMapper is an app on Android to do this: https://play.google.com/store/apps/details?id=cellmapper.net.cellmapper&hl=en_US https://play.google.com/store/apps/details?id=cellmapper.net...
  - instagib 2y ago
    *3001#12345#* Put it in your dialer for detailed info. It used to be able to show real signal levels instead of bars once activated but now this is where we are. Need a little test kit to get the full info. May need to re-enter or reboot to exit the mode. Depends on the phone. I’ve been in a lot of bad signal areas proposing repeaters or diagnosing issues and used it.
mminer237 2y ago
All major US carriers do.

slowmotiony 2y ago

How do you forward a text?

orra 2y ago
Often there's a long click menu in your SMS app to do it. But all that really does is copy the body into a new SMS. There's no metadata to indicate it's forwarded, as you suspect. This means texting 7726 is a two step process. First you send the body. You immediately get a response asking for the phone number of the spam sender, so then you sent that.
- lxgr 2y ago
  Does the phone number even matter for tracing? As far as I understand SMS delivery, it’s not authenticated at all. I suppose it can be used to help the operator identify the actual incoming message in their logs?
  - toast0 2y ago
    Source number authorization depends on how the messages get to the carrier and how the carrier has things setup. At the end of the day, there's a lot of trust though; and a lot of connections would be difficult/expensive to confirm that the connection is authorized to send messages from the sources they're using. Think of BCP38 for IP spoofing, but for number spoofing. If you get an appropriate country mobile number from a carrier in that country, are you going to pay for a portability lookup to confirm that carrier is the authorized carrier for that number? Does that carrier check source numbers for all of the connections they have? Some of the aggregators are good at checking sources, and some aren't, but aggregators are often authorized to send messages from many different countries, so they're likely to have their connections unchecked, because keeping the list updated is hard. It's like IP transit, but a lot worse.

doophus 2y ago

Would this even work in the article's situation, where someone's MITMing SMS?

mdp2021 2y ago
If you believe the cell you are under is compromised, further action should be performed under a different cell. Actually, I would like to have an option to identify the cells devices are connected to.
- mminer237 2y ago
  CellMapper is an app on Android to do this: https://play.google.com/store/apps/details?id=cellmapper.net.cellmapper&hl=en_US https://play.google.com/store/apps/details?id=cellmapper.net...
- instagib 2y ago
  *3001#12345#* Put it in your dialer for detailed info. It used to be able to show real signal levels instead of bars once activated but now this is where we are. Need a little test kit to get the full info. May need to re-enter or reboot to exit the mode. Depends on the phone. I’ve been in a lot of bad signal areas proposing repeaters or diagnosing issues and used it.

mminer237 2y ago

All major US carriers do.