Free Practice Questions for CompTIA CS0-003 Exam

Time synchronization is the process of ensuring that all systems in a network have the same accurate time, which is essential for correlating data points from different sources. If the system has an issue with time synchronization, the analyst may have difficulty matching events that occurred at the same time or in a specific order. Access rights, network segmentation, and invalid playbook are not directly related to the issue of correlating data points. Verified References: [CompTIA CySA+ CS0-002 Certification Study Guide], page 23

Updating the system firmware and reimaging the hardware is the best action to perform to remediate the infected device, as it helps to ensure that the device is restored to a clean and secure state and that any traces of malware are removed. Firmware is a type of software that controls the low-level functions of a hardware device, such as a motherboard, hard drive, or network card. Firmware can be updated or flashed to fix bugs, improve performance, or enhance security. Reimaging is a process of erasing and restoring the data on a storage device, such as a hard drive or a solid state drive, using an image file that contains a copy of the operating system, applications, settings, and files. Reimaging can help to recover from system failures, data corruption, or malware infections. Updating the system firmware and reimaging the hardware can help to remediate the infected device by removing any malicious code or configuration changes that may have been made by the malware, as well as restoring any missing or damaged files or settings that may have been affected by the malware. This can help to prevent further damage, data loss, or compromise of the device or the network. The other actions are not as effective or appropriate as updating the system firmware and reimaging the hardware, as they do not address the root cause of the infection or ensure that the device is fully cleaned and secured. Installing an additional malware scanner that will send email alerts to the analyst may help to detect and remove some types of malware, but it may not be able to catch all malware variants or remove them completely. It may also create conflicts or performance issues with other security tools or systems on the device. Configuring the system to use a proxy server for Internet access may help to filter or monitor some types of malicious traffic or requests, but it may not prevent or remove malware that has already infected the device or that uses other methods of communication or propagation. Deleting the user profile and restoring data from backup may help to recover some data or settings that may have been affected by the malware, but it may not remove malware that has infected other parts of the system or that has persisted on the device.

Cloud-specific misconfigurations are security issues that arise from improper or inadequate configuration of cloud resources, such as storage buckets, databases, virtual machines, or containers. Cloud-specific misconfigurations may not be detected by the current scanners that are designed for on-premises environments, as they may not have the visibility or access to the cloud resources or the cloud provider’s APIs. Therefore, one of the implications that should be considered on the new hybrid environment is that cloud-specific misconfigurations may not be detected by the current scanners.

The scan output where ports are marked as “closed” suggests the use of ahalf-open or SYN scan. In a SYN scan, the scanner sends only the initial SYN packet and does not complete the TCP handshake. If a SYN-ACK is received, the port is open; if a RST is received, it is closed. This scanning method is also referred to as astealth scanand is frequently used to avoid detection.

The command in question involves an encoded PowerShell command, which is typically used by attackers to obfuscate malicious scripts. To decode and understand the payload, one would need to decode the base64 encoded string. This is why option A is the correct answer, as 'base64 -d' is a command used to decode data encoded with base64. This process will reveal the plaintext of the encoded command, which can then be analyzed to understand the actions that the attacker was attempting to perform. Option B is risky and not advised without a controlled and isolated environment. Option C is not safe because executing unknown or suspicious code with administrator privileges could cause harm to the system or network. Option D also poses a risk of executing potentially harmful code on an analyst’s workstation.

The best action that the SOC manager can recommend to help ensure new employees are accountable for following the company policy is to require all new employees to sign a user agreement to acknowledge the company security policy. A user agreement is a document that defines the rights and responsibilities of the users regarding the use of the company’s systems, networks, or resources, as well as the consequences of violating the company’s security policy. Signing a user agreement can help ensure new employees are aware of and agree to comply with the company security policy, as well as hold them accountable for any breaches or incidents caused by their actions or inactions.

PID 2264 (bash running as root) is suspicious because:

It has elevated privileges (root user).

Bash (command-line shell) is running with high CPU usage (14.0%), which is unusual unless actively being used.

If unauthorized, an attacker could be exfiltrating data via command-line methods like scp, wget, or custom scripts.

Why Not Other Options?

B (34218 - Xorg) → Xorg is a display server for GUI; no signs of exfiltration.

C (34834 - Cinnamon) → Cinnamon is a desktop environment, not a threat.

D (35963 - xrdp) → xrdp is a remote desktop service, expected behavior.

Increasing training and awareness for all staff is the best way to address the issue of employees being enticed to assist attackers by visiting specific websites and running downloaded files when prompted by phone calls. This issue is an example of social engineering, which is a technique that exploits human psychology and behavior to manipulate people into performing actions or divulging information that benefit the attackers. Social engineering can take many forms, such as phishing, vishing, baiting, quid pro quo, or impersonation. The best defense against social engineering is to educate and train the staff on how to recognize and avoid common social engineering tactics, such as:

Verifying the identity and legitimacy of the caller or sender before following their instructions or clicking on any links or attachments

Being wary of unsolicited or unexpected requests for information or action, especially if they involve urgency, pressure, or threats

Reporting any suspicious or anomalous activity to the security team or the appropriate authority

Following the organization’s policies and procedures on security awareness and best practices

Official References:

https://partners.comptia.org/docs/default-source/resources/comptia-cysa-cs0-002-exam-objectives

https://www.comptia.org/certifications/cybersecurity-analyst

https://www.comptia.org/blog/the-new-comptia-cybersecurity-analyst-your-questions-answered

Based on the list of hosts and their functions, DCEast01, which is a Domain Controller, would be the most pivotal in the distribution of an encryption binary via Group Policy. Domain Controllers are responsible for security and administrative policies within a Windows Domain. Group Policy is a feature of Windows that facilitates a wide range of advanced settings that administrators can use to control the working environment of user accounts and computer accounts. Group Policy can be used to deploy software, which in this case would be the encryption binary of the ransomware. SQL01 is a database server and unlikely to be used for this purpose. WK10-Sales07 and WK7-Plant01 are client machines, and HQAdmin9, although it is a network admin laptop, would not typically be used to distribute policies across a network.

In case of a phishing attack, it’s crucial to review what actions were taken by the employee and analyze the phishing email to understand its nature and impact.References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 6, page 246; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 6, page 255.