CS0-002 Exam Dumps - CompTIA CySA+ Questions and Answers

If an analyst observes evidence of an attack but cannot find an exploit that adequately explains the observations, it may indicate the presence of a zero-day vulnerability, which is an unknown vulnerability that attackers can exploit to gain unauthorized access to systems. In such cases, traditional security tools may not be able to detect or prevent the attack. Therefore, the analyst should investigate further to identify and mitigate the vulnerability to prevent further exploitation.

Supervised and unsupervised machine-learning algorithms are two types of machine-learning methods that are used in cybersecurity applications. Machine learning is a branch of artificial intelligence that enables systems to learn from data and improve their performance without explicit programming.

Supervised machine-learning algorithms are trained on labeled data, which means that each data point has a known outcome or class. Supervised algorithms learn to map input data to output data by finding patterns or rules from the training data. Supervised algorithms require security analyst feedback to provide labels for the data and evaluate the accuracy of the algorithm’s predictions. Examples of supervised machine-learning algorithms are classification and regression.

Unsupervised machine-learning algorithms are trained on unlabeled data, which means that each data point has no known outcome or class. Unsupervised algorithms learn to discover hidden structures or patterns from the data without any guidance or feedback. Unsupervised algorithms do not require security analyst feedback, as they do not rely on predefined labels or outcomes. Examples of unsupervised machine-learning algorithms are clustering and anomaly detection.

Requests identified by a threat intelligence service with a bad reputation are likely to be malicious or suspicious, as they originate from sources that are known to be involved in cyberattacks or other malicious activities. These requests may indicate that an attacker is trying to exploit a vulnerability or perform reconnaissance on the web server.

Requests sent from the same IP address using different user agents are also likely to be malicious or suspicious, as they indicate that an attacker is trying to evade detection or bypass security controls by changing their browser or device identification. These requests may indicate that an attacker is using automated tools or scripts to scan or attack the web server.

An incident response plan should cover the most important and likely scenarios that could compromise the security and operations of an organization. According to various sources of best practices123, an incident response plan should start by conducting a risk assessment to identify potential threats and vulnerabilities, and prioritize the critical systems that need to be protected and restored in case of an incident. Focusing on incidents that affect critical systems ensures that the incident response plan covers the most severe and impactful situations that could harm the organization’s mission, reputation, or legal obligations.

Static analysis is the process of reviewing malware files without running them, by using tools such as hex editors, strings, and signature scanners. Static analysis can help extract basic information from malware files, such as file type, size, checksum, metadata, imports, exports, etc. Static analysis can also help identify known malware samples based on their signatures or hashes.

Logical segmentation is a technique that divides a network into smaller, isolated segments based on logical criteria, such as function, role, or application. Logical segmentation can be implemented using various technologies, such as VLANs, subnets, virtual firewalls, or software-defined networking (SDN). Logical segmentation can enhance the security of a network by reducing the attack surface, limiting the lateral movement of threats, enforcing the principle of least privilege, and facilitating the monitoring and auditing of network traffic12.

Firewall is a device or software that filters and controls the incoming and outgoing network traffic based on predefined rules or policies. Firewall can be deployed at the network perimeter or within the network to create internal zones or segments. Firewall can protect a network from unauthorized access, malicious attacks, or data exfiltration by allowing or blocking traffic based on the source, destination, port, protocol, or application3 .

To best provide the protection that meets the requirements of the security engineer, each product line should be logically segmented and firewalled to control inbound and outbound connectivity. This way, each product line can be secured using a single posture that is consistent and manageable. Each product line can also communicate with the other lines in a least privilege method by allowing only the necessary traffic and blocking the rest. Access to each product line from the rest of the network can be strictly controlled by applying firewall rules that restrict or limit the traffic based on the business needs.

The analyst should request a configuration change on the company’s public DNS as the next step, as this can help resolve the issue of marketing campaigns being filtered by the customer’s email servers. The issue is caused by SPF validation failures, which indicate that the marketing partner’s email address is not authorized to send emails on behalf of the company’s domain. SPF stands for Sender Policy Framework, and it is a mechanism that allows domain owners to specify which IP addresses or hosts are allowed to send emails using their domain name. SPF validation is done by checking the SPF record of the sender’s domain in the public DNS, and comparing it with the IP address or host name of the sender’s email server. To fix this issue, the analyst should request a configuration change on the company’s public DNS to add or update the SPF record to include the marketing partner’s email address or IP address as a valid sender.

Lessons learned is a critical stage of incident response that involves evaluating the effectiveness of the response, identifying gaps and areas for improvement, and updating the incident response plan accordingly1. Company leadership should be involved in this process to ensure they are aware of the incident, its impact, and the actions taken to prevent or mitigate future incidents. Additionally, company leadership can provide support and guidance for implementing the recommendations from the lessons learned session2.

The security analyst should implement port security with one MAC address per network port of the switch. This will help prevent possible physical attacks on the network access layer, such as MAC flooding or MAC spoofing. Port security is a feature that allows a switch to limit the number of MAC addresses that can be learned on a specific port. By setting the limit to one MAC address per port, the switch will only allow traffic from the device that is connected to that port, and drop any traffic from other devices that try to use that port. This will prevent attackers from connecting unauthorized devices to the network or impersonating legitimate devices by changing their MAC addresses3.

A vulnerability scan is a process of identifying and assessing known vulnerabilities in a system or network using automated tools or software1 A vulnerability scan can help improve the security posture of a vulnerability management program by detecting and prioritizing potential weaknesses that could be exploited by attackers. To increase the security posture of a vulnerability scan, the following actions can be taken:

• Expand the ports being scanned to include all ports: This means scanning all possible ports on a system or network, not just the well-known or commonly used ones. This can help discover more vulnerabilities that may be hidden or overlooked on less frequently used ports.
• Increase the scan interval to a number the business will accept without causing service interruption: This means scanning more frequently or regularly, but not so often that it causes performance issues or downtime for the system or network. This can help keep up with new vulnerabilities that may emerge over time and reduce the window of opportunity for attackers.
• Enable authentication and perform credentialed scans: This means using login credentials or SSH keys on an asset to get deeper access to its data, processes, configurations, and vulnerabilities2 This can help discover more vulnerabilities that cannot be seen from the network, such as insecure versions of software or poor security permissions.