SIM swapping bypasses two-factor authentication by stealing your phone number.

**How it works:** 1. Attacker gathers info about you (social media, data breaches, phishing) 2. They call your carrier pretending to be you, claiming lost/stolen phone 3. They convince the carrier to transfer your number to their SIM 4. Your phone loses service; their phone receives your calls and texts 5. They receive all your 2FA codes 6. They reset passwords and drain accounts

**What gets compromised:** - Bank accounts (password reset via SMS) - Cryptocurrency exchanges and wallets - Email accounts - Social media accounts - Any account using SMS 2FA

**How they get carrier access:** - Social engineering customer service - Phishing your carrier account PIN - Bribing carrier employees (documented cases) - Using personal info from data breaches