When a legacy device is no longer receiving updates or patches, it is considered to be at the end of life (EOL)
. This means the manufacturer has ceased support for the device, and it will no longer receive updates, security patches, or technical assistance. EOL devices pose security risks and are often decommissioned or replaced.
* End of support may seem similar but typically refers to the cessation of technical support, whereas EOL means the device is fully retired.
* End of business and End of testing do not apply in this context.

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."

A Certificate Signing Request (CSR) is a request sent to a certificate authority (CA) to issue an SSL certificate. The CSR contains information like the public key, which will be part of the certificate.References:
Security+ SY0-701 Course Content, Security+ SY0-601 Book.

The final step in the incident response process is "Lessons learned." This step involves reviewing and analyzing the incident to understand what happened, how it was handled, and what could be improved. The goal is to improve future response efforts and prevent similar incidents from occurring. It's essential for refining the incident response plan and enhancing overall security posture.
References = CompTIA Security+ SY0-701 study materials, particularly in the domain of incident response and recovery.