A web-based CRM system that is directly accessed by customers via the Internet should be hosted in a secure and isolated environment to protect it from external threats and unauthorized access. A web-based CRM system should also be reliable, trusted, and backed up regularly1.
Hosting the system on an external third-party service provider's servers (A) or a hybrid-cloud platform managed by a service provider (B) may not be a concern for the auditor if the service provider has adequate security measures and service level agreements in place. The auditor should verify the security controls and contractual terms of the service provider before trusting them with the CRM data23.
Hosting the system within a demilitarized zone (DMZ) of a corporate network is a common practice to provide an extra layer of security to the CRM system from untrusted networks, such as the Internet. A DMZ is a perimeter network that isolates the CRM system from the internal network and filters the incoming traffic from the external network using a security gateway4567.
Hosting the system within an internal segment of a corporate network (D) is a concern for the auditor because it exposes the CRM system and the internal network to potential attacks from the Internet. The CRM system should not be directly accessible from the Internet without a DMZ or a firewall to protect it. This could compromise the confidentiality, integrity, and availability of the CRM data and the internal network78.

The best sampling method to use for verifying the adequacy of an organization's internal controls and being concerned about potential circumvention of regulations is B. Random sampling. Random sampling is a method of selecting a sample from a population in which each item has an equal and independent chance of being selected1. Random sampling reduces the risk of bias or manipulation in the sample selection, and ensures that the sample is representative of the population. Random sampling can be used for both attribute and variable sampling, which are two types of audit sampling that test for the occurrence rate or the monetary value of errors, respectively2.

The observation that should be of most concern to the auditor when reviewing security controls related to collaboration tools for a business unit responsible for intellectual property and patents is that employees can share files with users outside the company through collaboration tools. Collaboration tools are software or hardware devices that enable users to communicate, cooperate, and coordinate with each other on a common task or project. Collaboration tools can facilitate information sharing and knowledge exchange among users, but they can also pose security risks if not properly controlled or managed. Employees can share files with users outside the company through collaboration tools, as this can compromise the security and confidentiality of intellectual property and patents, which are valuable and sensitive assets of the organization. Employees may share files with unauthorized or untrusted users who may misuse or disclose the intellectual property and patents, either intentionally or unintentionally. This can cause harm or damage to the organization, such as loss of competitive advantage, reputation, revenue, or legal rights. Training was not provided to the department that handles intellectual property and patents is a possible observation that could indicate a security issue related to collaboration tools for a business unit responsible for intellectual property and patents, but it is not the most concerning one. Training is anactivity that educates and instructs users on how to use collaboration tools effectively and securely, such as how to access, share, store, and protect information using collaboration tools. Training was not provided to the department that handles intellectual property and patents, as this can affect the awareness and competence of users on collaboration tools, and increase the likelihood of errors or mistakes that may compromise the security or quality of information. However, this observation may not be directly related to collaboration tools, as it may apply to any information system or resource used by the department. Logging and monitoring for content filtering is not enabled is a possible observation that could indicate a security issue related to collaboration tools for a business unit responsible for intellectual property and patents, but it is not the most concerning one. Logging and monitoring are processes that record and analyze the events or activities that occur on an information system or network, such as user actions, system operations, data changes, errors, alerts, etc. Content filtering is a technique that blocks or allows access to certain types of information based on predefined criteria or rules, such as keywords, categories, sources, etc. Logging and monitoring for content filtering is not enabled, as this can affect the auditability, accountability, and visibility of collaboration tools, and prevent detection or investigation of security incidents or violations related to information sharing using collaboration tools. However, this observation may not be specific to collaboration tools, as it may affect any information system or network that uses content filtering. The collaboration tool is hosted and can only be accessed via an Internet browser is a possible observation that could indicate a security issue related to collaboration tools for a business unit responsible for intellectual property and patents, but it is not the most concerning one. A hosted collaboration tool is a type of cloud-based service that provides collaboration functionality over the Internet without requiring installation or maintenance on local devices. An Internet browser is a software application that enables users to access and interact with web-based content or services. The collaboration tool is hosted and can only be accessed via an Internet browser, as this can affect the availability and reliability of collaboration tools, and introduce security or privacy risks for information sharing using collaboration tools. However, this observation may not be unique to collaboration tools, as it may apply to any cloud-based service that uses an Internet browser.

The best recommendation to prevent unauthorized access to a highly sensitive data center by piggybacking or tailgating is to use an airlock entrance. An airlock entrance is a type of access control system that consists of two doors that are interlocked, so that only one door can be opened at a time. This prevents an unauthorized person from following an authorized person into the data center without being detected. An airlock entrance can also be integrated with other security measures, such as biometrics, card readers, or PIN pads, to verify the identity and authorization of each person entering the data center.
Biometrics (option A) is a method of verifying the identity of a person based on their physical or behavioral characteristics, such as fingerprints, iris scans, or voice recognition. Biometrics can provide a high level of security, but they are not sufficient to prevent piggybacking or tailgating, as an unauthorized person can still follow an authorized person who has been authenticated by the biometric system.
Procedures for escorting visitors (option B) is a policy that requires all visitors to the data center to be accompanied by an authorized employee at all times. This can help prevent unauthorized access by visitors, but it does not address the risk of piggybacking or tailgating by other employees or contractors who may have legitimate access to the building but not to the data center.
Intruder alarms (option D) are devices that detect and alert when an unauthorized person enters a restricted area. Intruder alarms can provide a deterrent and a response mechanism for unauthorizedaccess, but they are not effective in preventing piggybacking or tailgating, as they rely on the detection of the intruder after they have already entered the data center.
References: 1: CISA Certification | Certified Information Systems Auditor | ISACA 2: CISA Certified Information Systems Auditor Study Guide, 4th Edition 3: CISA - Certified Information Systems Auditor Study Guide [Book]