CompTIA CS0-002 - CompTIA CySA+ Certification Exam (CS0-002)

Automating the use of a hashing algorithm after verified users make changes to their data is an appropriate course of action to verify that a user’s data is not altered without the user’s consent. Hashing is a technique that produces a unique and fixed-length value for a given input, such as a file or a message. Hashing can help to verify the data integrity by comparing the hash values of the original and modified data. If the hash values match, then the data has not been altered without the user’s consent. If the hash values differ, then the data may have been tampered with or corrupted .

Sinkholing is a technique for manipulating data flow in a network; you redirect traffic from its intended destination to the server of your choosing. It can be used maliciously, to steer legitimate traffic away from its intended recipient, but security professionals more commonly use sinkholing as a tool for research and reacting to attacks1 Sinkholing can help prevent any impact to the company from similar attacks in the future by redirecting the malicious traffic from the compromised assets to a sinkhole server, where it can be monitored, analyzed, or blocked. Sinkholing can also prevent the compromised assets from communicating with their command and control servers or exfiltrating data to remote destinations.

Fuzzing is a technique that involves sending random, malformed, or unexpected inputs to an application to trigger errors, crashes, or vulnerabilities. Fuzzing can be used to test the robustness and security of software, especially when the source code is not available or the input format is complex1. Fuzzing can also simulate abnormal user behavior, such as entering invalid data, clicking on random buttons, or sending malicious requests2.

Fuzzing tools are software programs that automate the process of generating and sending inputs to the application under test. There are different types of fuzzing tools, such as black-box fuzzers, white-box fuzzers, and grey-box fuzzers, depending on the level of information and feedback they have about the application1. Some examples of fuzzing tools are AFL, Peach, and [Sulley].

Polymorphic methods are techniques that allow fuzzing tools to modify or mutate the inputs in different ways, such as changing the length, value, type, or structure of the data. Polymorphic methods can increase the diversity and effectiveness of the inputs and help discover more bugs or vulnerabilities in the application .

Therefore, using fuzzing tools with polymorphic methods would be the best approach to test a new application that simulates abnormal user behavior to find software bugs. This approach would generate a large number of inputs that cover various scenarios and edge cases and expose any flaws or weaknesses in the application’s functionality or security.

A buffer overflow is a type of attack that exploits a vulnerability in an application or program that does not properly check the size or boundaries of an input. A buffer overflow occurs when an attacker supplies more data than the buffer can hold, causing the excess data to overwrite adjacent memory locations. This can result in unpredictable behavior, such as crashes, errors, data corruption, or execution of malicious code2 The tool that the analyst ran against the executable supplied an input that was too long for the buffer allocated by the executable. This caused a buffer overflow in the executable’s memory, as indicated by the error message “Segmentation fault (core dumped)”.

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.

Disabling the Telnet service would harden the server by removing an insecure protocol that transmits data in cleartext and could allow unauthorized access to the server. Changing the SSH port to a non-standard port would harden the server by reducing the exposure to brute-force attacks or port scans that target the default SSH port (22). Uninstalling the DNS service, performing a vulnerability scan, changing the server’s IP to a private IP address, or blocking port 80 with the host-based firewall would not harden the server or could affect its functionality as a web server. Reference: https://www.cisco.com/c/en/us/support/docs/ip/access-lists/13608-21.html

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.

Threat intelligence is a collection and analysis of information about current and emerging threats and vulnerabilities that affect an organization’s assets and operations. Threat intelligence can help to guide risk evaluation activities by providing context, prioritization and recommendations for mitigating firmware vulnerabilities. For example, threat intelligence can help to identify which firmware vulnerabilities are actively exploited in the wild, which ones have high severity or impact, and which ones have available patches or workarounds. Implementing critical updates after proper testing can help to ensure that the firmware updates are trusted, compatible and effective. Testing can help to verify the integrity and authenticity of the firmware updates, as well as their compatibility with the existing system configuration and functionality. Testing can also help to identify any issues or conflicts that may arise from applying the firmware updates and resolve them before deployment12.

SIEM software is a tool that provides a single centralized platform for the collection, monitoring, and management of security-related events and log data from across the enterprise1. SIEM software can help security analysts detect, investigate, and respond to threats, as well as comply with regulations and standards.

IPS stands for Intrusion Prevention System. It is a device or software that monitors network traffic and blocks or modifies malicious packets before they reach their destination2. IPS can help security analysts prevent attacks, protect sensitive data, and reduce network downtime.

A security analyst working for a biotechnology lab that is planning to release details about a new cancer treatment would most likely be monitoring for A. Intellectual property loss. Intellectual property (IP) refers to the creations of the mind, such as inventions, designs, artistic works, or trade secrets3. IP loss occurs when someone steals, leaks, or misuses the IP of an organization without authorization.

The biotechnology lab’s new cancer treatment is an example of IP that has high value and potential impact on the market and society. Therefore, the security analyst would want to protect it from competitors, hackers, or other malicious actors who might try to access it illegally or sabotage it. The security analyst would use SIEM software and IPS to monitor for any signs of unauthorized access, data exfiltration, or tampering with the lab’s network or systems.

User acceptance testing is a process of verifying that a software application meets the requirements and expectations of the end users before it is released to production. User acceptance testing can help to validate the functionality, usability, performance and compatibility of the software application with real-world scenarios and feedback . User acceptance testing can involve various teams, such as developers, testers, customers and stakeholders.