SIM Swap Fraud: Definition, How It Works, and How to Avoid It

Be careful! Your phone number can be taken over by fraudsters to gain access to your banking account and other important accounts. This type of fraud is called SIM swap fraud.

Unlike phishing, where victims must click on a fraudulent link to fall into the trap, SIM swap fraud occurs when scammers take control of a victim’s phone number. The impact? All personal data, including OTP (One-Time Password), can fall into the hands of criminals. Scary, right?

So, how does SIM swap fraud happen, and how can you protect yourself from it? Here’s everything you need to know.

What Is SIM Swap Fraud?

SIM swap fraud is a cybercrime where fraudsters take over a victim’s phone number to gain access to accounts linked to that number. By controlling the victim’s SIM card, fraudsters can receive OTPs sent via SMS, making it easier for them to break into banking accounts, digital wallets, e-commerce accounts, and social media profiles.

Why does taking over a SIM card expose personal information? A Subscriber Identity Module (SIM) card is a small chip inserted into a phone to identify the user on a mobile network. It stores important data such as phone numbers, network information, and contacts. The main function of a SIM card is to connect a device to a mobile network, make calls, send messages, and access the internet.

Now, imagine if a fraudster took over your SIM card without your knowledge. Suddenly, someone else has access to your banking account. If this happens, you may no longer have control over your own accounts.

How Does SIM Swap Fraud Happen?

There are two main stages in SIM swap fraud:

Stage 1: Collecting the Victim’s Personal Information

Fraudsters obtain the victim’s personal details—such as full name, national ID number, date of birth, address, and login credentials—through the following methods:

1. Phishing Emails or SMS

• Fraudsters send fake emails or text messages pretending to be from a mobile network provider.
• Victims are asked to update their account details by clicking a fraudulent link and entering their personal information.

2. Malware

• Scammers send links containing malware. If the victim clicks on it, the malware records their activity, including login credentials and answers to security questions.

3. Social Media & Dark Web

• Many people unknowingly share personal information on social media.
• Personal data leaks are also frequently sold on the dark web and used for fraudulent activities.

Stage 2: Taking Over the Victim’s Phone Number

Once fraudsters have enough personal information, they contact the mobile carrier, impersonate the victim, and claim their SIM card (which actually belongs to the victim) has been lost or damaged.

Because the fraudsters already have the victim’s personal details, they can easily answer security questions from the mobile carrier. Once the process is successful, the carrier activates a new SIM card for the fraudster, transferring the victim’s phone number to the fraudster’s device. This means all calls and messages, including OTPs, will now be received by the fraudster instead of the victim.

What Can Fraudsters Do with Your Phone Number?

Once fraudsters gain control of a victim’s phone number, they can:

1. Access Bank Accounts and Conduct Unauthorized Transactions

• Using the victim’s phone number, fraudsters can log into mobile banking apps.
• If the victim relies on SMS OTPs for authentication, fraudsters can reset passwords and receive OTPs directly to their new SIM card.
• Fraudsters can drain bank accounts, make unauthorized transfers, and apply for financial transactions.

2. Take Over Social Media Accounts

• Fraudsters can log into WhatsApp, Instagram, Facebook, and other accounts.
• Once inside, they can change passwords, contact the victim’s friends to ask for money under false pretenses, or spread phishing links.

3. Apply for Online Loans or Credit

• If the victim’s phone number is registered with loan providers, fraudsters can apply for new loans or even create new loan accounts.

4. Use the Victim’s Number for Other Fraudulent Activities

• Fraudsters can scam the victim’s contacts via WhatsApp or SMS, asking for money transfers.
• The victim’s phone number could also be used to register for illegal services, exposing them to further fraud risks.

Signs That You Might Be a Victim of SIM Swap Fraud

If you experience any of the following, be cautious:

• Suddenly losing network signal, even though the mobile network is functioning normally.
• Unable to make calls or send SMS messages.
• Receiving notifications of transactions you didn’t make.
• Unable to log into online accounts, such as banking, e-commerce, or social media.

If you notice any of these signs, contact your mobile provider and relevant institutions immediately to prevent further losses.

How to Protect Yourself from SIM Swap Fraud

1. Keep Your Personal Information Private

• Avoid oversharing personal details on social media.
• Never enter personal data on suspicious websites or forms.

2. Beware of Phishing Attempts

• Never click on links from suspicious emails or text messages.
• Scammers use fake mobile towers (BTS spoofing) to impersonate legitimate mobile carriers, making it easier for victims to trust them.

3. Avoid SMS OTP-Based Authentication

• SMS OTP is no longer secure because it can be intercepted through SIM swap fraud and phishing.
• Some banks in Singapore have already eliminated SMS OTPs due to security risks.

A Safer Authentication Solution: FaceToken and PhoneToken by VIDA

To combat threats like SIM swap fraud, phishing, and account takeovers, VIDA offers a more secure authentication method without OTPs—FaceToken and PhoneToken.

VIDA FaceToken: Biometric-Based Authentication

FaceToken combines liveness detection, face matching, and device authentication in one verification step. With this system:

• Only the real user’s face can log in.
• Protects against deepfake and injection attacks.
• More secure than SMS OTP authentication.

VIDA PhoneToken: Device-Based Authentication

PhoneToken uses Public Key Infrastructure (PKI) technology to secure users’ devices. With this method:

• Only registered devices can be used for authentication.
• Eliminates the risk of OTP theft via SIM swap.
• Prevents phishing, as there’s no OTP code for fraudsters to steal.

SIM swap fraud is a serious threat that can lead to bank account theft, loss of digital accounts, and significant financial damage. Relying solely on SMS OTP is no longer safe, as fraudsters can easily intercept it.

The best way to stay protected is to switch to stronger authentication methods, such as VIDA FaceToken and VIDA PhoneToken, which provide greater security and fraud resistance.