Changing default passwords is a critical first step after acquiring new devices. Default credentials are widely known and publicly documented, so changing them prevents unauthorized access using this information.
[Reference:, CompTIA Security+ SY0-701 Official Study Guide, Domain 3.1: "Changing default passwords prevents attackers from exploiting publicly available device information.", Exam Objectives 3.1: “Implement secure network architecture concepts.”, , , , , , ]
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