Orca Crypto
Security term

SIM swap

An attacker takes over your phone number to defeat SMS two factor authentication.

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Updated 2026-08-303 min readDefinition
Definition

An attacker takes over your phone number to defeat SMS two factor authentication.

The attacker convinces your carrier to port your number to their SIM. Every SMS code then goes to them, including exchange login and withdrawal codes.

This is why SMS is the weakest form of two factor authentication, and why it should never protect an exchange account holding real money.

In practice

Use an authenticator app or a hardware security key instead of SMS wherever the option exists.

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