SIM swapping can involve simply moving an old phone number to a new SIM card. It is often done for practical reasons, such as losing a phone, getting a new one that needs a different SIM size, having a damaged SIM card, or finding a better mobile plan. In these cases, SIM swapping is completely normal.

Thanks to services like SIM swapping and mobile number portability, people can keep the same phone number for years, even decades. There’s no need to inform everyone about a number change, get a new SIM, transfer the number, and life goes on as usual.

However, the ease of transferring a phone number to a new SIM card has made it a target for fraudsters. This type of fraud can cause individuals to lose money and harm the reputation of companies like MNOs and banks.

How does this scam work?

SIM swap fraud is a cybercrime in which fraudsters exploit the SIM card swapping process to steal personal and financial information. They can access social media and bank accounts by gaining control over a victim’s phone number.

Here’s a simple way to understand it:

• Criminals obtain your mobile phone number.
  
• They contact your mobile network operator (MNO) pretending to be you.
  
• They trick the MNO into activating a new SIM card with your phone number.
  
  

Once the new SIM card is active, the scammers receive all Two-Factor Authentication (2FA) and One-Time Pins (OTPs) messages sent to your number. This gives them access to your accounts , which rely on your phone number for security.

Identifying and Preventing SIM Swap Fraud:

Mobile operators can identify SIM swap fraud by observing changes to a user’s phone number (MSISDN) and the unique SIM card identifier, the International Mobile Subscriber Identity (IMSI) number. The IMSI is specific to each SIM card and stays the same even if the phone number (MSISDN) is moved to another SIM card.

For example, when a bank sends OTP codes for authentication, it can check for recent SIM swaps. This ensures the verification code isn’t sent to a scammer who has obtained a new SIM card with the same phone number as the targeted account.

Final Words:

SIM swap fraud is a severe threat that can cause financial losses and harm reputations. However, by taking proactive steps, individuals and businesses can minimise the consequences and risks.

To prevent SIM swap fraud, mobile network operators (MNOs) should regularly monitor for SIM swaps by tracking changes in a user’s phone number (MSISDN) and unique SIM card identifier (IMSI). This proactive approach helps to identify suspicious activity at an early stage and prevent potential scams.