A private cloud deployment model is the most appropriate when the requirement is for 'need-to- know' access, as it offers a more secure environment with resources dedicated to a single organization. It can be hosted on-premises or off-premises but is maintained on a private network, ensuring greater control over the data, security, and compliance when compared to other cloud models.

A hybrid model allows the database to remain on-premises within the company's SAN while the application workload is hosted by a third-party provider, meeting both location and operational requirements.

To identify DDoS attacks against a CMS service, a cloud engineer should monitor network flow logs. These logs provide data about the IP traffic going to and from network interfaces in a public cloud, which is essential for detecting the increased traffic volumes typically associated with DDoS attacks.

For vulnerabilities with a high CVSS score and a network attack vector, the most effective and direct mitigation action is to patch the operating systems. Patching addresses the specific vulnerabilities that have been identified and helps to secure the servers against the known exploits that could take advantage of these CVEs.

Load-based scaling automatically adjusts resources in response to real-time utilization thresholds (such as 75-80%). This ensures resources are scaled dynamically when demand increases, preventing performance degradation.