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2. どこでも一意のパスワードを使用する
Credential stuffing — trying breached passwords against other accounts — is responsible for the majority of account compromises. A password manager (NordPass, Bitwarden) generates and stores unique passwords automatically.
A credit freeze prevents anyone — including identity thieves — from opening new credit accounts in your name. Free at all three bureaus (Equifax, Experian, TransUnion). Can be temporarily lifted when you need to apply for credit. Takes about 15 minutes total.