During a penetration testing engagement, a tester targets the internet-facing services used by the client.

An external assessment focuses on testing the security of internet-facing services. Here’s why option C is correct:

External Assessment: It involves evaluating the security posture of services exposed to the internet, such as web servers, mail servers, and other public-facing infrastructure. The goal is to identify vulnerabilities that could be exploited by attackers from outside the organization’s network.

Segmentation: This type of assessment focuses on ensuring that different parts of a network are appropriately segmented to limit the spread of attacks. It’s more relevant to internal network architecture.

Mobile: This assessment targets mobile applications and devices, not general internet-facing services.

Web: While web assessments focus on web applications, the scope of an external assessment is broader and includes all types of internet-facing services.

References from Pentest:

Horizontall HTB: Highlights the importance of assessing external services to identify vulnerabilities that could be exploited from outside the network​​.

Luke HTB: Demonstrates the process of evaluating public-facing services to ensure their security​​.

Conclusion:

Option C, External, is the most appropriate type of assessment for targeting internet-facing services used by the client.

=================