CISA Exam Dumps - Certified Information Systems Auditor

The most likely application input control that would detect data input errors in the customer account number field during the processing of an accounts receivable transaction is a validity check. A validity check is a type of application control that verifieswhether the data entered in an application matches a predefined set of values or criteria1. For example, a validity check can compare the customer account number entered by the user with a list of existing customer account numbers stored in a database, and reject any input that does not match any of the valid values2.

The other options are not as likely to detect data input errors in the customer account number field, because they do not compare the input with a predefined set of values or criteria. A limit check is a type of application control that verifies whether the data entered in an application falls within a specified range or limit1. For example, a limitcheck can ensure that the amount entered for an invoice does not exceed a certainmaximum value2. A parity check is a type of application control that verifies whether the data entered in an application has an even or odd number of bits1. For example, a parity check can detect transmission errors in binary data by adding an extra bit to the data and checking whether the number of bits is consistent3. A reasonableness check is a type of applicationcontrol that verifies whether the data entered in anapplication is logical or sensible based on other related data or information1. Forexample, a reasonableness check can ensure that the date entered for an order is not in the future or before the date of creation of the customer account2. References:

What are application controls? Definition, examples and best practices1

General Control Vs Application Control: Key Differences and Example …4

Parity Check - an overview | ScienceDirect Topics

The correct answer is B. To identify material information security vulnerabilities.

The primary purpose of a formal information security audit is to independently evaluate whether security controls are adequate and effective, and to identify material vulnerabilities, weaknesses, or risks that could affect the confidentiality, integrity, and availability of information assets. ISACA states that audit objectives often center on substantiating the existence of internal controls to minimize business risk, and ISACA’s cybersecurity audit guidance describes reviewing gathered data to identify potential security vulnerabilities or risk and documenting findings and recommendations.

Option A is important, but it is more directly related to information security governance and strategy than the primary purpose of a formal audit. Option C is not correct because reducing software licensing cost is a cost-management activity, not the main objective of an information security audit. Option D is also incorrect because monitoring security team productivity is a management function, not the primary purpose of an independent audit.

This question maps mainly to Information Systems Auditing Process because it concerns why an audit is conducted: to provide independent assurance, identify material issues, and support risk-based recommendations.

Access controls for source libraries are the features of a library control software package that would protect against unauthorized updating of source code. Access controls are the mechanisms that regulate who can access, modify, or delete the source code stored in the source libraries. Source libraries are the repositories that contain the source code files and their versions. By implementing access controls for source libraries, the library controlsoftware package can prevent unauthorized or malicious users from tampering with the source code and compromising its integrity, security, or functionality1.

The other options are not as effective as access controls for source libraries in protecting against unauthorized updating of source code. Option A, required approvals at each life cycle step, is a good practice but may not be sufficient to prevent unauthorized updates if the approval process is bypassed or compromised. Option B, date and time stamping of source and object code, is a useful feature but may not prevent unauthorized updates if the date and time stamps are altered or ignored. Option D, release-to-release comparison of source code, is a helpful feature but may not prevent unauthorized updates if the comparison results are not reviewed or acted upon.

 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. 

Ransomwareis a type of malicious software that encrypts the victim’s data and demands a ransom for its decryption1. Ransomware attacks can cause significant damage to an organization’s operations, reputation, andfinances1. Therefore, it is important to mitigate the impact of ransomware attacks by implementing effective prevention and recovery strategies.

One of the best ways to mitigate the impact of ransomware attacks is to back up data frequently12345. Data backups are copies of the organization’s data that are stored in a separate location or medium, such as an external harddrive, cloud storage, or tape2. Data backupscan help the organization restore its data in case of a ransomware attack, without paying the ransom or losing valuable information2. Data backups shouldbe performed regularly, preferably daily or weekly, depending on the criticality and volume of the data2. Data backups should also be tested periodically to ensure their integrity and usability2.

The other options are not as effective as backing up data frequently in mitigating the impact of ransomware attacks. Invoking the disaster recovery plan (DRP) is a reactive measure that can help the organization resume its operations after a ransomware attack, but it does not prevent or reduce the damage caused by the attack3. Paying the ransom is not a recommended option, as it does not guarantee the decryption of the data or the deletion of the stolen data by the attackers. Paying the ransom also encourages further attacks and funds criminal activities14. Requiring password changes for administrative accounts is a good security practice, but it is not sufficient to prevent or recover from ransomware attacks. Ransomware attacks can exploit other vulnerabilities, such as phishing emails, outdated software, or weak network security15.