91–100 of 174 posts
Follow up, does the IMEI number get broadcast when you connect, or is it a searchable bit of information accessible by apps, et al?
Im wondering how anonymous you can be if youre making all the right privacy moves, but your phone is still essentially giving you up because your IMEI number is traceable back to you.
These people are not trying to do anything particularly nefarious but they do it so that they can use a phone or tablet plan in a router. Unlimited or high GB plans for routers and hotspots are expensive and there are not many options.
There are lots of reasonably priced, easy to get unlimited phone and tablet plans but if you put a phone SIM in a router it might work for while until the carrier detects that you have the SIM in an unauthorized device. The "solution" to that is to activate on a spare phone and then change the router IMEI to match the phone. Don't use both devices at the same time. The carrier now thinks the router is a phone.
The legally of it is somewhat unclear so it's talked about quietly on various forums using words like "magic configuration", "giving your router an identity crisis" etc.
It's a bit of a cat and mouse game because IMEI is probably not the only way to identify an unauthorized device but so far it seems to be the main way.
Is there any entity or procedure that actually proves what a phone is what it claims to be? Unfortunately, neither IMEI, Serial Number or a combination of both can assert this. I bought a Samsung S24 a week ago off Facebook Marketplace. It was in the box and everything. I cross checked both the IMEIs and also the Serial Number with the #06# test. I even checked them online. Did all the tests, #0 # and even downloaded…
The carrier can ID the device type by the radio layer itself at the PHY layer.
Earlier quoted context omitted.
They are primarily used for configuring your visual voicemail lol. Stop the hyperbolic statements.
Could you elaborate on this? What is a 'visual voicemail'? What would a 'silent SMS' have to do with that?
Many carriers implement this via "silent SMS" + IMAP (the same IMAP as for emails). The device will send an activation or status message to the carrier's visual voicemail number and the carrier will respond with an SMS containing the IMAP credentials.
The version of this I'm familiar with is T-Mobile's old CVVM protocol. During initial setup, the device will send a text message containing "Activate:dt=6" to the number 122 and T-Mobile will reply with (in decoded form):
pw_len=4-9
vs_len=10
u=
pw=IMAP password>
rc=0
st=R
ipt=148
srv=e7.vvm.mstore.msg.t-mobile.com
lang=1|2|3|4
g_len=180
curl -v imaps://:@e7.vvm.mstore.msg.t-mobile.com/
rc=0
st=B
srv=vvm.mstore.msg.t-mobile.com
In case anyone is interested, the vvmd wiki (visual voicemail implementation for Linux phones) has information on how several carriers implement VVM: https://gitlab.com/kop316/vvmplayer/-/wikis/Visual-Voicemail.... AT&T's is especially nasty.
Earlier quoted context omitted.
> Radio firmware and state machines have always had weird bugs, and even when it conforms to standards (some of which are extremely interpretable), does very weird things in the real world. Pre-smartphone, being able to update phone and radio firmware was extremely rare, so it was common for the networks instead to implement workarounds on a manufacturer or handset basis. Having a hardware ID that identified this was…
Only two digits? What could possibly go wrong... again.
Couple of thoughts > The combination of the ICCID and the IMSI basically tells the mobile network, “hey, this person paid for a plan.” As far as I remember, the ICCID never actually appears in standard network messaging. It might be possible for the network to request it, but it's not part of a standard 2/3/4/5g attach. The piece seemed to miss two major uses for the IMEI (or I missed it when reading), which were wor…
[dead]
The phone/baseband doesn’t talk to the network in AT commands.
Earlier quoted context omitted.
In Kazakhstan, when a phone is used on a mobile network for the first time, the IMEI of the phone gets locked to that mobile network and that sim card. When you buy the sim card, they photocopy your passport/ID card. No other sim will work in it until you take that photo ID/passport to the mobile companies office to have it unlocked. The photo id (even if expired) becomes the unlock code for the phone. Made phone the…
> Made phone theft drop to pretty much zero Use a nuke to kill a fly?
Couple of thoughts > The combination of the ICCID and the IMSI basically tells the mobile network, “hey, this person paid for a plan.” As far as I remember, the ICCID never actually appears in standard network messaging. It might be possible for the network to request it, but it's not part of a standard 2/3/4/5g attach. The piece seemed to miss two major uses for the IMEI (or I missed it when reading), which were wor…
> As far as I remember, the ICCID never actually appears in standard network messaging. Yeah, that would be the IMSI (which a given SIM card can have multiple of, e.g. for switching to a more beneficial home network while roaming!) The ICCID is useful for identifying a given physical SIM card (e.g. so that the phone can link a given user-selected profile name to it/the associated phone line for a "preferred line for…
Always thought it would make more sense to have a dedicated "test number" for this purpose. Probably with some rate limiting.
Earlier quoted context omitted.
> As far as I remember, the ICCID never actually appears in standard network messaging. Yeah, that would be the IMSI (which a given SIM card can have multiple of, e.g. for switching to a more beneficial home network while roaming!) The ICCID is useful for identifying a given physical SIM card (e.g. so that the phone can link a given user-selected profile name to it/the associated phone line for a "preferred line for…
At least in the US, the 911 infrastructure is dated. In older systems, your caller ID is sent using in-band DTMF tones, which are decoded by the dispatch computer. On newer E-911 systems they get some additional digital address data from the telephone network, but the record format wasn't designed with VoIP or cellular in mind. So in those cases, the telephone network sends a virtual number and the dispatch computer…
Technology under pressure looks a lot like biology.
Earlier quoted context omitted.
There is no privacy concern, really, as this is unique to the device, not subscriber, and only shared with the network operator, who obviously already "tracks" the subscriber through the SIM , which contains the subscriber identifier (IMSI). On the other hand, the IMEI in principle makes tracking and disabling of stolen devices easy. By the way, in the UK it is actually an offence to change the IMEI [1] [1] https://w…
The IMEI also allows a network operator to track a device across multiple sims. And I think it's also shared with roaming operators if roaming happens.