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The IMEI Code: Your phone’s other number

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121–130 of 174 posts

Re: The IMEI Code: Your phone’s other number

#121
post #56

Earlier quoted context omitted.

Yeah, they seem to be confusing that with IMSIs or ICCIDs, which are indeed namespaced by mobile country code and international calling code respectively. Based on what other commenters have already pointed out, this seems to be a quite sloppily researched article.

This is interesting - I hadn't noticed this, but my Chinese (Xiaomi) phone indeed has an IMEI starting with 86, which is China's dialling code. Perhaps a coincidence. The ICCID starts 8944 - not sure of the significance of the 89, but 44 is the UK, where my SIM card (and me) comes from.

89 is the MII (major industry identifier) according to ISO/IEC 7812 (https://en.wikipedia.org/wiki/ISO/IEC_7812). First digit 8 includes the telecom industry.

Re: The IMEI Code: Your phone’s other number

#122
post #58
post #53

Earlier quoted context omitted.

They can track you with or without the IMEI. Next identifier is the IMSI read from your SIM card and I guess you're not replacing it every day...

Disclaimer: used to work in SIGINT, so please treat anything I say about this with appropriate skepticism. There are people that for various reasons do cycle out their SIM card frequently as a means to avoid tracking. This is ineffective. Changing the IMEI/discarding devices entirely is more effective.

But if you change IMEI and use the same SIM card, you're still trackable as if nothing changed, right? The IMSI would be the same. I guess you need to change both at the same time...

Re: The IMEI Code: Your phone’s other number

#124
post #16

Android defaults to sending the IMSI (SIM ID) to Google. > SUPL is used as part of the A-GPS (Assisted GPS) system to get a faster Time to First Fix. The problem is that Android's implementation automatically sends the IMSI (ID of the SIM card) to the SUPL provider for no apparent reason. And because Google is the default provider it's a big breach of privacy. https://github.com/Magisk-Modules-Alt-Repo/supl-replacer…

I document this more in depth here https://divestos.org/misc/gnss.txt

Re: The IMEI Code: Your phone’s other number

#125

Earlier quoted context omitted.

In Australia, you can report your phone as stolen and it becomes IMEI blocked, not able to be used on Australian phone networks. https://amta.org.au/lost-and-stolen-mobiles/ https://amta.org.au/check-the-status-of-your-handset/

sounds like a dos vector. is there a lot of abuse of this?

sounds like considering linking to a social security number would be a good idea.. any reasons this ain't commonplace?

Re: The IMEI Code: Your phone’s other number

#126

Also a rare UK success story in brute force lawmaking. People used to hack phones IMEI all the time, lots of utils available. Then anything relating to changing an imei was heavily punished and it all stopped. Nobody would host a utility or a guide or even mention it on a forum. If you did mention it you were banned. It was almost instant.

That doesn't sound good at all.

"Success story" does not imply that the greater good was successful

Re: The IMEI Code: Your phone’s other number

#127

Earlier quoted context omitted.

I have heard of people calling emergency numbers to test if a phone is working, but never a country making that impossible. Here, I had always assumed that repeated nuisance callers would be investigated to see if there's an actual problem, and charged with a crime if they're doing it for no good reason. Always thought it would make more sense to have a dedicated "test number" for this purpose. Probably with some rat…

A lot of telcos used to have phone numbers you could call that would just say the number you're calling from (like with a computerized voice). I forget what this was called, but it was talked about in phreaking community or so on. Not sure if these "caller identifier" phone numbers are still around today though.

800-444-4444 still works. Even starts with "thank you for calling MCI"

Re: The IMEI Code: Your phone’s other number

#129

Fun fact: Lots of cellular modem/routers have the easy ability to change IMEI. Doing so is a fairly common practice in the rural internet community. i.e., those using cellular for their internet access either because cable / fiber or an official cellular option like T-Mobile home internet is unavailable or they're mobile in an RV. These people are not trying to do anything particularly nefarious but they do it so tha…

glorious reminds me of changing mac address to get around data caps in the student dorm network

Or getting online with an Ethernet network that refuses to connect with an unauthorized MAC.

Re: The IMEI Code: Your phone’s other number

#130

Earlier quoted context omitted.

I have heard of people calling emergency numbers to test if a phone is working, but never a country making that impossible. Here, I had always assumed that repeated nuisance callers would be investigated to see if there's an actual problem, and charged with a crime if they're doing it for no good reason. Always thought it would make more sense to have a dedicated "test number" for this purpose. Probably with some rat…

A lot of telcos used to have phone numbers you could call that would just say the number you're calling from (like with a computerized voice). I forget what this was called, but it was talked about in phreaking community or so on. Not sure if these "caller identifier" phone numbers are still around today though.

They're called ANACs - automatic number announcement circuits.
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