The auditor's best course of action is to document the finding and explain the risk of having administrator accounts with inappropriate security settings. This is because the auditor's role is to identify and report the issues, not to fix them or request others to fix them. The auditor should also communicate the impact of the finding, such as the possibility of unauthorized access, data tampering, or denial of service attacks. The auditor should not assume the responsibility of the IT manager or the DBA, who are in charge of changing the security parameters or disabling the accounts. References:
* CISA Review Manual (Digital Version), Chapter 4, Section 4.2.21
* CISA Online Review Course, Domain 1, Module 3, Lesson 32

For an organization that has plans to implement web-based trading, it would be most important for an IS auditor to verify that the organization's information security plan includes security requirements for the new application. Security requirements are statements that define what security features and functions are needed to protect the confidentiality, integrity, and availability of the web-based trading application and its data.
Security requirements should be identified and documented during the planning phase of the application development life cycle, before any design or coding activities take place. Attributes for system passwords, security training prior to implementation, and firewall configuration for the web server are also important aspects of information security, but they are not as essential as security requirements for ensuring that the web- based trading application meets its security objectives.

The risk that is most affected by this oversight is audit risk. Audit risk is the risk that the auditor may express an inappropriate opinion or conclusion based on the audit evidence obtained. Audit risk consists of inherent risk, control risk, and detection risk. Inherent risk is the risk that material errors or frauds exist in the audited area before considering the effectiveness of internal controls. Control risk is the risk that the internal controls fail to prevent or detect material errors or frauds. Detection risk is the risk that the auditor fails to identify material errors or frauds using the audit procedures performed. In this case, the auditor has overlooked evidence that could contradict a conclusion of the audit, which increases the detection risk and consequently the audit risk. References:
* CISA Review Manual (Digital Version), Chapter 2, Section 2.31
* CISA Online Review Course, Domain 1, Module 1, Lesson 32