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Sim Swap Meaning

Jun 28, 2024 | Updated Jun 28, 2024
A SIM swap is a type of scam where a hacker takes control of your phone number by tricking your mobile carrier into transferring it to their SIM card.

What Is Sim Swapping?

Sim swap is a type of scam in which criminals convince mobile phone providers to transfer your phone number to a SIM card that they control. This allows them to receive your calls and texts, including authentication codes. Hackers often achieve this by impersonating the target when they call the phone carrier’s customer service, tricking them into transferring the number. Sometimes, they even bribe phone company employees to carry out the switch.

Once the hackers control the phone number, they can request temporary login codes from online services you use like your social media accounts or online banking. These codes are sent as text messages as part of the companies’ processes to help users recover lost passwords. Moreover, attackers can bypass two-factor authentication (2FA) and gain access to your sensitive accounts, including crypto wallets.

High-profile examples include Ethereum’s co-founder, Vitalik Buterin’s recent Sim Swap encounter. On September 12, 2023, his account was compromised, and Buterin explained that a hacker manipulated T-Mobile, his telecom provider, to gain control of his phone number. 

Sim Swap Crypto Hack: How Can You Prevent It?

To protect yourself from SIM swap attacks, consider the following measures:

  • Enable Strong Authentication: Use hardware-based security keys like YubiKey for two-factor authentication instead of relying on SMS codes. 
  • Set Up a PIN or Passcode:  Add an extra layer of security with your mobile carrier by setting a PIN or passcode that must be provided for any SIM changes.
  • Avoid Sharing Personal Information: Be cautious about sharing personal details online, as hackers can use this information to impersonate you.
  • Monitor Your Accounts: Regularly check your bank, email, and cryptocurrency accounts for any unusual activity.
  • Use Unique Passwords: Ensure that all your online accounts have strong, unique passwords that are changed regularly.
  • Enable Alerts: Opt for additional notifications from your carrier when changes are made to your SIM card or phone number.
  • Consider Phoneless Authentication: Consider removing your phone number from the authentication process entirely for highly sensitive accounts.
  • Consider hardware devices for Crypto: To avoid unnecessary losses, it’s always best practice to use a hardware device to secure your crypto. Ledger devices are built specifically with user security in mind and have never been hacked.

Implementing these precautions can significantly reduce the risk of falling victim to a SIM swap attack and protect your valuable cryptocurrency assets.

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