Isaca CISA Practice Test - Questions Answers, Page 39

The best way to detect that a distributed denial of service (DDoS) attack is occurring is to use automated monitoring of logs.A DDoS attack disrupts the operations of a server, service, or network by flooding it with unwanted Internet traffic2.Automated monitoring of logs can help pinpoint potential DDoS attacks by analyzing network traffic patterns, monitoring traffic spikes or other unusual activity, and alerting administrators or security teams of any anomalies or malicious requests, protocols, or IP blocks3. Automated monitoring of logs can also help identify the source, type, and impact of the DDoS attack, and provide evidence for further investigation or mitigation.

The other options are not as effective as automated monitoring of logs for detecting DDoS attacks. Customer service complaints are an indirect and delayed indicator of a DDoS attack, as they rely on users reporting problems with accessing a website or service. Customer service complaints may also be caused by other factors unrelated to DDoS attacks, such as server errors or network issues. Server crashes are an extreme and undesirable indicator of a DDoS attack, as they indicate that the server has already been overwhelmed by the attack and has stopped functioning. Server crashes may also result in data loss or corruption, service disruption, or reputational damage. Penetration testing is a proactive and preventive measure for assessing the security posture of a system or network, but it does not detect ongoing DDoS attacks. Penetration testing may involve simulating DDoS attacks to test the resilience or vulnerability of a system or network, but it does not monitor real-time traffic or identify actual attackers.

ISACA CISA Review Manual 27th Edition (2019), page 254

How to prevent DDoS attacks | Methods and tools | Cloudflare2

Understanding Denial-of-Service Attacks | CISA3

Data classification is the process of organizing data into categories based on its sensitivity, value, and risk to the organization. Data classification helps to ensure that data is protected according to its importance and regulatory requirements. Data classification also enables data owners to make informed decisions about data access, retention, and disposal.

To implement a data classification program, it is most important to formalize data ownership. Data owners are the individuals or business units that have the authority and responsibility for the data they create or use. Data owners should be involved in defining the data classification levels, assigning the appropriate classification to their data, and ensuring that the data is handled according to the established policies and procedures. Data owners should also review and update the data classification periodically or when there are changes in the data or its usage.

The other options are not as important as formalizing data ownership when implementing a data classification program. Understanding the data classification levels is necessary, but it is not sufficient without identifying the data owners who will apply them. Developing a privacy policy is a good practice, but it is not specific to data classification. Planning for secure storage capacity is a technical consideration, but it does not address the business and legal aspects of data classification.

ISACA, CISA Review Manual, 27th Edition, 2020, page 247

Data Classification: What It Is and How to Implement It

Segregation of duties (SoD) is a key internal control that aims to prevent fraud and errors by ensuring that no single individual can perform incompatible or conflicting tasks within a business process. SoD reduces the risk of unauthorized or improper transactions, manipulation of data, or misappropriation of assets.

In the accounts payable department, SoD involves separating the following functions: invoice processing, payment authorization, payment execution, and reconciliation. For example, the person who approves an invoice should not be the same person who issues the payment or reconciles the bank statement.

One of the best ways to ensure appropriate SoD within the accounts payable department is to restrict program functionality according to user security profiles. This means that each user of the accounts payable system should have a unique login and password, and should only have access to the functions that are relevant to their role and responsibilities. For instance, an invoice processor should not be able to approve payments or modify vendor records. This way, the system can enforce SoD and prevent unauthorized or fraudulent activities.

The other options are not as effective as restricting program functionality according to user security profiles. Restricting access to update programs to accounts payable staff only is a general access control measure, but it does not address the SoD issue within the accounts payable department. Including the creator's user ID as a field in every transaction record created is a useful audit trail feature, but it does not prevent users from performing incompatible functions. Ensuring that audit trails exist for transactions is a detective control that can help identify and investigate any irregularities, but it does not prevent them from occurring in the first place.

Computer performance is the measure of how well a computer system can execute tasks and applications within a given time frame. Computer performance can be affected by various factors, such as hardware specifications, software configuration, network conditions, and user behavior. To analyze computer performance, it is important to use statistical metrics that can quantify the capacity utilization of the system resources, such as CPU, memory, disk, and network. These metrics can help identify the bottlenecks, inefficiencies, and anomalies that may degrade the performance of the system. Examples of such metrics include CPU utilization, memory usage, disk throughput, network bandwidth, and response time.

The other options are not as useful as statistical metrics when analyzing computer performance. An operations report of user dissatisfaction with response time is a subjective measure that may not reflect the actual performance of the system. Tuning of system software to optimize resource usage is a corrective action that can improve performance, but it is not a method of analysis. A report of off-peak utilization and response time is a limited snapshot that may not capture the peak performance or the average performance of the system.

What is Computer Performance?

How to Measure Computer Performance

Water sensors are devices that can detect the presence of water or moisture in a given area. They are often deployed below the floor tiles of a data center to monitor for any water leaks that may damage the equipment or cause electrical hazards. Water sensors can alert the data center staff or trigger an automatic response to prevent or mitigate the water leakage.

The other options are not likely to be deployed below the floor tiles of a data center. Temperature sensors and humidity sensors are usually deployed above the floor tiles to measure the ambient conditions of the data center and ensure optimal cooling and ventilation. Air pressure sensors are typically deployed at the air vents or ducts to monitor the airflow and pressure distribution in the data center.

Data Center Environmental Monitoring

Water Detection in Data Centers

Digital watermarks are hidden marks or codes that can be embedded into digital files, such as images, videos, audio, or documents. They can be used to identify the source, owner, or authorized user of the data, as well as to track any unauthorized copying or distribution of the data. Digital watermarks can help prevent data leakage by deterring potential leakers from sharing sensitive data or by providing evidence of data leakage if it occurs.

The other options are not as effective as digital watermarks in preventing data leakage. Ensuring that paper documents are disposed securely can reduce the risk of physical data leakage, but it does not address the digital data leakage that is more prevalent in today's environment. Implementing an intrusion detection system (IDS) can help detect and respond to cyberattacks that may cause data leakage, but it does not prevent data leakage from insiders or authorized users who have legitimate access to the data. Verifying that application logs capture any changes made can help audit and investigate data leakage incidents, but it does not prevent them from happening in the first place.

What is Data Leakage?

What is Digital Watermarking?

The first step in assessing the controls within a newly implemented call center is to evaluate the operational risk associated with the call center. This will help the IS auditor to identify the potential threats, vulnerabilities, and impacts that could affect the call center's objectives, performance, and availability. The evaluation of operational risk will also provide a basis for determining the scope, objectives, and approach of the audit. The other options are possible audit procedures, but they are not the first step in the audit process.Reference:ISACA Frameworks: Blueprints for Success,CISA Review Manual (Digital Version)

The most reliable follow-up procedure to determine if management has resolved the finding of non-sequential purchase order numbers is to inspect the system settings and transaction logs to determine if sequential order numbers are generated. This will provide direct evidence of the system's functionality and compliance with the audit recommendation. The other options are less reliable because they rely on indirect evidence or information obtained from management, which may not be accurate or complete.Reference:CISA Review Manual (Digital Version),Standards, Guidelines, Tools and Techniques

When reviewing a data classification scheme, it is most important for an IS auditor to determine if the security criteria are clearly documented for each classification. This will help the IS auditor to evaluate if the data classification scheme is consistent, comprehensive, and aligned with the organizational objectives and regulatory requirements.The security criteria should define the level of confidentiality, integrity, and availability for each data classification, as well as the corresponding controls such as access control, rights management, and cryptographic protection1. The other options are less important or incorrect because:

A . Each information asset is not necessarily assigned to a different classification.Data classification schemes usually have a limited number of categories, such as ''Sensitive,'' ''Confidential,'' and ''Public,'' and multiple information assets can belong to the same category2.

C . Senior IT managers are not necessarily identified as information owners.Information owners are typically the business units or functions that create, use, or maintain the information assets, and they may or may not be senior IT managers3.

D . The information owner is not required to approve access to the asset.The information owner is responsible for defining the access requirements and rules for the asset, but the actual approval of access requests may be delegated to other roles, such as data custodians or administrators3.Reference:Simplify and Contextualize Your Data Classification Efforts - ISACA,3.7: Establish and Maintain a Data Classification Scheme,Data Classification and Practices - NIST,CISA Exam Content Outline | CISA Certification | ISACA