2023.06.03

 

How secure is your SIM

 

SIM card enables you to use services from a Mobile Network Operator (MNO). From MNO perspective it will enable MNO to identify you as subscriber/ customer. With that in mind, SIM card in thief or hacker hand can cause financial and personal problem. SIM card is the key to the social media and bank accounts. With the advent of end-to-end encryption technology, two-way authentication is the new norm. When you log in to your account, an OTP (One-Time Password) is sent to your SIM card number. When you enter the OTP, you can log into your account, using social media, banks, payment portals, streaming services, and so forth. Now just imagine your SIM card in the wrong hands even for a few minutes.

SIM card security has become default capability since it’s produced. SIM card is physically protected and when using services on MNO network.

The PIN and PUK code.

PIN code consisting of 4 digits, is the access code to your SIM card, and therefore your access code to the MNO network. So it’s very important to keep your PIN secure. PIN stands for Personal Identification Number. Usually it come as 0000 or 1234 in fix number and can come as random number as well. If the PIN code is enabled you must enter this code every time you switch on your mobile.

So again, the PIN can be enabled or disabled as per MNO’s policy. When it is disabled you don’t need to put it every time you turn on the mobile phone.

PUK code which stands for Personal Unblocking Key, is an 8-digit code used to unlock your SIM card if you have entered the wrong PIN code three times in a row.

You can find your PIN and PUK code printed on the card to which your SIM card was attached.In some MNO’s SIM the PIN and  PUK code can also be found under the silver layer of SIM card. If the PIN and PUK code not printed on the card then you have to ask it from MNO.

It’s not only access to MNO’s services which protected by PIN code. Inside the SIM there are some files which contain SIM information. Offcourse these files are protected by security named Access Condition. And there are some keys to open the Access Condition. One of them is PIN code.

That’s why if a thief or hacker knows your PIN code, he/ she is only on halfway to make clone of your SIM and gain access to MNO’s services.



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