CompTIA CySA+ Practice Test (CS0-003)

This is an example of a compensating control. Since the primary control (encryption at rest) cannot be implemented due to technical constraints, the organization has put alternative measures in place (strict ACLs, DLP, monitoring) to provide an equivalent level of protection and satisfy the security requirement's intent. While some of the individual measures are preventative, 'compensating control' is the most accurate and encompassing term for the overall strategy. Corrective controls are used to restore systems after an incident has occurred. Managerial controls relate to overarching security governance, such as policies and risk assessments, rather than specific technical implementations like these.

A compensating control for mitigating the risk posed by an unpatchable legacy system should involve measures that provide security equivalent to the original fix. Implementing a firewall rule to block specific attack vectors helps limit exposure to vulnerabilities while a more permanent solution is being developed. Although routine vulnerability scanning is important, it does not directly mitigate the specific identified vulnerability. Disabling unused services improves security but may not address the specific vulnerability. Increasing logging and monitoring is valuable but is more of a detective control rather than a preventive one.

The primary configuration file for the Apache HTTP server is usually located at '/etc/httpd/conf/httpd.conf' or '/etc/apache2/apache2.conf' depending on the Linux distribution. This file contains directives that configure the overall behavior and modules of the Apache server. Understanding the location of these critical files is important for any security operations task involving system hardening and monitoring for unauthorized changes. The other options provided are common locations but linked to other services or aspects of the OS, making them incorrect for this context.

Implementing network segmentation as a compensating control is the best immediate action because it will help contain any potential future breaches by limiting lateral movement across the network, providing time to restore the primary defense mechanisms. Updating the incident response plan is a post-incident activity and so it does not provide immediate risk mitigation. Conducting a root cause analysis is a vital post-incident activity, but it is not immediately helpful in controlling the current vulnerability. Extending VPN access would likely increase the attack surface and is not a suitable compensating control under the circumstances.

Integrating automated alerting systems can significantly reduce MTTR by ensuring that relevant teams are notified of any incidents promptly. This minimizes the delay between detection and response initiation. While regular training and detailed documentation are important for overall readiness and improving MTTR, they do not have as immediate and direct an impact on reducing MTTR as automated alerting. Relying solely on human intervention generally leads to slower response times compared to automated systems.

The IT operations team should be informed promptly as they are directly responsible for managing and maintaining the production servers. Involving them early ensures prompt remediation efforts without causing unnecessary business process interruptions. While other stakeholders such as the compliance team, customers, and PR team may also need to be informed, their involvement is secondary in the immediate technical assessment and remediation.

Detective controls are designed to identify and record security incidents after they occur, helping organizations to respond to breaches and mitigate damage. They do not prevent incidents but rather focus on detection and recording. Preventive controls are intended to stop security incidents before they happen, whereas corrective controls focus on restoring systems and data after an incident has occurred.

The correct answer is 'Breakpoints'. Breakpoints allow the analyst to halt the program's execution at specified points, which enables the inspection of the state of the program at those moments. This can be vital in identifying the cause of crashes or other unexpected behaviors in the binary. 'Watchpoints' are used to monitor changes in specific variables, 'Single-stepping' is used for examining code execution line-by-line, and 'Core dumps' provide a snapshot of the program's memory at the time of crash, but do not provide the same level of interactive inspection as breakpoints.

When the same vulnerability resurfaces after patching and the scanner has been validated, the most common cause is that something in the build or configuration-management process is rolling back or reinstalling the vulnerable version. Gold images, automated configuration-management tools (such as Ansible, Chef, Puppet, or SCCM), or container/base-image redeployments can overwrite the fixed package with an older one, effectively undoing the patch. Until the baseline image or repository is updated, every redeployment or scheduled configuration run will reintroduce the flaw. The other explanations are less likely: firewall changes were ruled out, the scanner has been verified to detect patched systems accurately, and a single reboot would not repeatedly reinstall an outdated package on multiple hosts.

Periodic and predictable traffic patterns are classic signs of beaconing, which is often used in command and control communication by malware. The best action to take is to analyze the packet contents to identify any signs of malicious communication or anomalies. Checking for unusual port usage and validating the destination server's reputation are also important steps, but analyzing the packet contents will provide the most direct evidence of beaconing.

Accepting the risk is the most appropriate action in this scenario because the immediate remedial action, such as updating or patching, would lead to significant operational downtime impacting the business. Since the vulnerabilities are not being actively exploited, the impact is low, and there are strong monitoring and compensating controls in place, the risk can be acknowledged and accepted until a more suitable solution is found that minimizes business disruption. On the other hand, transferring the risk would involve shifting the risk to another party, which is not relevant in the context of managing software vulnerabilities internal to an organization. Mitigating the risk by taking action to decrease its occurrence is not the recommended option in this scenario, as it implies attempting to patch or update the application, which is not presently viable due to operational constraints. Avoiding the risk by eliminating it completely would typically require discontinuing use of the vulnerable application, which is not suitable for a mission-critical application.

The correct first step in a well-structured incident response plan is to identify and validate the incident. This involves confirming the unauthorized access attempts and gathering initial evidence. Without proper identification, any subsequent steps, such as containment or eradication, may be misdirected. Steps like notifying law enforcement, isolating the affected system, and informing management are important but should occur after proper identification and validation to ensure an appropriate and effective response.

Malware is often designed to detect sandbox environments and behave nondescriptly to evade detection. The correct answer, 'The malware detects the sandbox environment and is programmed to avoid execution within it,' accounts for this evasion technique. Malware authors program their malicious code to look for signs of a virtualized or analysis environment to prevent security professionals from studying their behavior, thus hindering the malware analysis process. Alternative incorrect answers are plausible scenarios but do not cater specifically to the given context of malware detection avoidance.

Law enforcement should be engaged when the facts suggest criminal activity (for example, data theft, extortion, or network intrusion that crosses jurisdictions) or when statutes or regulations mandate external reporting. This ensures that any potential crime is investigated, preserves admissible evidence, and keeps the organization in regulatory compliance. Routine security events or purely internal matters do not automatically require police involvement, and premature disclosure can hamper containment or create jurisdictional conflicts. Options B, C, and D each describe situations that either lack evidence of criminality or defer unnecessarily and therefore are not appropriate triggers for contacting law enforcement.

Reverse engineering is the process of analyzing a system or software to understand its design, architecture, and functionality when the source code is unavailable. It is the primary method used to analyze the behavior of malware from an executable file. Fuzzing is an automated testing technique that involves providing invalid or unexpected data to a program to find crashes and vulnerabilities, not to understand its overall logic. Static code analysis typically refers to the analysis of source code, which is unavailable in this scenario. While some static analysis can be performed on binaries (e.g., disassembly), reverse engineering is the broader, more appropriate term for the analyst's goal. Port scanning is a network reconnaissance technique used to identify open ports on a host, which is irrelevant to analyzing the internal workings of a file.