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Account Security · 5 min read
Security Risks: Two-Factor Authentication on Abandoned Numbers
Why leaving an old phone number attached to email, banking, or crypto accounts invites catastrophic takeover.
The Zombie 2FA Vulnerability
Over 60% of people who change phone numbers forget to remove the old number from at least one critical web account. When that number is recycled and assigned to a stranger months later, that stranger can initiate SMS password resets on services like PayPal, Venmo, or Apple ID.
Always audit password managers and service profiles before discontinuing any cellular line.
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