SIM swap fraud question

[magicfoot]

I read yet another story about SIM swap fraud in the news today.

Each SIM has an IMSI number, an international serial number. Vodacom requires access to a central database to acquire the phone number matched to this IMSI.

Does this mean that whoever is committing SIM cloning fraud is matching a cell number to a new IMSI, or a different IMSI ? If this is correct this would mean that that there are two IMSIs with the same cellphone number.

Is the above even possible ? How does this cloning work ? Is the IMSI number on the physical SIM being copied to another SIM in order to create the clones ?

 

[supersunbird]

Swapping... not cloning. You are bringing the word cloning into something where no one else has used the word cloning.

After the swap, there is still only one IMSI (the new one) with the phone number.

 

[magicfoot]

OK. Thanks for the correction in terminology. I am used to our multi-SIM devices where we regularly "swap" out SIMs if they are defective, or swapping to a different MNO, etc., hence the use of the word clone.

From what you say then, the IMSI from physical SIM 1 is placed onto physical SIM2 ?

 

[supersunbird]

No, the telephone number of associated with physical SIM1 is put onto physical SIM2. The SIMs will still each have their own IMSI.

Very advanced criminals might do the proper SIM cloning thing but I think they will have bigger targets than normal peoples bank accounts.

All the SIM swap crims want is to get your internet banking One Time Pin SMS (with some going to the added benefit to themselves of making many international calls and using data Out Of Bundle even cause what do they care).