CompTIA CySA+ CS0-003 Exam Questions and Answers PDF

Input validation vulnerabilities occur when an application fails to properly validate or sanitize user input, allowing malicious data to be processed. This can lead to various attacks, most notably cross-site scripting (XSS).

Option A:DNS poisoning

Incorrect Choice:DNS poisoning involves corrupting the DNS cache to redirect users to malicious sites. It is not related to input validation vulnerabilities.

Option B:Pharming

Incorrect Choice:Pharming redirects users from legitimate websites to fraudulent ones, typically through DNS poisoning or host file manipulation. It is not directly related to input validation.

Option C:Phishing

Incorrect Choice:Phishing involves tricking individuals into providing sensitive information through deceptive emails or websites. It exploits human behavior rather than technical input validation flaws.

Option D:Cross-site scripting

Correct Choice:Cross-site scripting (XSS) attacks occur when an application includes untrusted data in a web page without proper validation or escaping. This allows attackers to execute malicious scripts in users' browsers, leading to data theft, session hijacking, or defacement. Remediating input validation vulnerabilities is essential to prevent XSS attacks.

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.

A Cloud Access Security Broker (CASB) would have reduced the complexity of identity and access management in cloud-based assets. CASBs provide visibility into cloud application usage, data protection, and governance for cloud-based services.

The suspicious line in the web server logs is an attempt to execute a command on the server, indicating a command injection attack.References: CompTIA CySA+ Study Guide: Exam CS0-003, 3rd Edition, Chapter 5, page 197; CompTIA CySA+ CS0-003 Certification Study Guide, Chapter 5, page 205.