Isaca Updated CISA Exam Questions and Answers by rogan

 When reviewing an enterprise architecture (EA) department’s decision to change a legacy system’s components while maintaining its original functionality, an IS auditor should understand the current business capabilities delivered by the legacy system, as this would help to evaluate whether the change is justified, feasible, and aligned with the business goals and needs. The proposed network topology to be used by the redesigned system, the data flows between the components to be used by the redesigned system, and the database entity relationships within the legacy system are technical details that are less relevant for an IS auditor to understand when reviewing this decision. References: CISA Review Manual (Digital Version), Chapter 3, Section 3.2

 An external assessment of network vulnerability is a process of identifying and evaluating the weaknesses and risks that affect the security and availability of a network from an outsider’s perspective. The most important factor to verify during this process is the completeness of network asset inventory, which is a list of all the devices, systems, and software that are connected to or part of the network. A complete and accurate network asset inventory can help identify the scope and boundaries of the network, the potential attack vectors and entry points, the critical assets and dependencies, and the existing security controls and gaps. Without a complete network asset inventory, an external assessment of network vulnerability may miss some important assets or vulnerabilities, leading to inaccurate or incomplete results and recommendations.

References:

1 explains what is an external vulnerability scan and why it is important to have a complete network asset inventory.

2 provides a guide on how to conduct a full network vulnerability assessment and emphasizes the importance of knowing the network assets.

3 compares internal and external vulnerability scanning and highlights the need for a comprehensive network asset inventory for both types.

 A weakness in change management is the most likely cause of an incorrect version of source code being amended by a development team. Change management is the process of controlling and documenting changes to IT systems and software. It ensures that changes are authorized, tested, and implemented in a controlled manner. If change management is weak, there is a risk of using outdated or incorrect versions of source code, which can lead to errors, defects, or security vulnerabilities in the software. 

The most effective way to detect an intrusion attempt is to periodically review log files, which record the activities and events on a system or network. Log files can provide evidence of unauthorized access attempts, malicious activities, or system errors. Configuring the router as a firewall, using smart cards with one-time passwords, and installing biometrics-based authentication are preventive controls that can reduce the likelihood of an intrusion, but they do not detect it. References: ISACA CISA Review Manual 27th Edition, page 301