CompTIA CAS-004 - CompTIA SecurityX Certification Exam

An immutable system is a system that does not change after it is deployed. Any changes or updates are done by creating a new system from a common image or template and replacing the old one. An immutable system meets the requirements of storing data outside of the VMs, preventing unauthorized modifications to the VMs, and deploying a new VM if a change needs to be done. An immutable system can improve the security, reliability, and consistency of the VMs by avoiding configuration drift, human errors, or malicious tampering. An immutable system can also simplify the deployment process and enable faster recovery from failures. Verified References:

https://cloudinfrastructureservices.co.uk/vm-types-for-devops-pets-vs-cattle-vs-immutable/

https://www.digitalocean.com/community/tutorials/what-is-immutable-infrastructure

A tabletop exercise is a type of testing plan that is used to discuss disaster recovery scenarios with representatives from multiple departments within an incident response team but without taking any invasive actions. A tabletop exercise is a simulation of a potential disaster or incident that involves a verbal or written discussion of how each department would respond to it. The purpose of a tabletop exercise is to identify gaps, weaknesses, or conflicts in the disaster recovery plan, and to improve communication and coordination among the team members.

OPC (Open Platform Communications) and Modbus are two common protocols used for industrial control systems (ICS). OPC is a standard that allows different devices and applicationsto exchange data in a vendor-neutral way. Modbus is a serial communication protocol that enables devices to send and receive commands and data over a network. Modbus has two variants: Modbus TCP/IP, which uses TCP port 502 for communication, and Modbus RTU/ASCII, which uses serial ports.

To allow an OPC server to communicate with a Modbus server that is controlling electrical relays, the security engineer should recommend restricting inbound traffic so that only the OPC server is permitted to reach the Modbus server on port 502. This configuration would:

Permit the OPC server to send commands and data to the Modbus server using Modbus TCP/IP protocol over port 502.

Limit operational disruptions, by preventing unauthorized or malicious access to the Modbus server from other sources.

Due to the limitations within the Modbus protocol, such as lack of encryption and authentication, restricting inbound traffic is a necessary security measure to protect the integrity and availability of the ICS.

The EDR output shows the process tree of the ransomware infection. The root node is NO-AV.exe, which is a malicious executable that disables antivirus software and downloads the DearCry ransomware. The NO-AV.exe process was launched on cpt-ws026 by a user named John. The DearCry.exe process was then launched on cpt-ws026 by NO-AV.exe and propagated to other devices via SMB. Therefore, the ransomware originated from cpt-ws026 and NO-AV.exe. Verified References:

https://www.microsoft.com/security/blog/2021/03/12/analyzing-dearcry-ransomware-the-first-attack-to-exploit-exchange-server-vulnerabilities/

https://www.crowdstrike.com/blog/dearcry-ransomware-analysis/

The company should implement an EV certificate and HSTS on its new website. An EV certificate provides the highest level of web identity validation by requiring extensive verification of the organization’s identity and domain ownership. HSTS enforces encryption of all web transactions by redirecting HTTP requests to HTTPS and preventing users from accepting invalid certificates. These solutions would enhance the security and trustworthiness of the website without increasing complexity or expenditure significantly. Verified References:

https://www.entrust.com/digital-security/certificate-solutions/products/digital-certificates/tls-ssl-certificates

https://learn.microsoft.com/en-us/azure/active-directory/develop/access-tokens

The browser is the application that the security analyst should patch first, given that all the applications have equally high CVSS scores. CVSS stands for Common Vulnerability Scoring System, which is a method for measuring the severity of vulnerabilities based on various factors,such as access conditions, impact, and exploitability. CVSS scores range from 0 to 10, with higher scores indicating higher severity. However, CVSS scores alone are not sufficient to determine the patching priority, asthey do not account for other factors, such as the likelihood of exploitation, the exposure of the system, or the criticality of the data. Therefore, the security analyst should also consider the context and the risk of each application when deciding which one to patch first. In this case, the browser is likely to be the most exposed and frequently used application by the network administrator, and also the most likely entry point for an attacker to compromise the system or access the SSO web portal. Therefore, patching the browser first can reduce the risk of a successful attack and protect the system and the data from further damage. Verified References:

https://nvd.nist.gov/vuln-metrics/cvss

https://www.darkreading.com/risk/vulnerability-severity-scores-make-for-poor-patching-priority-researchers-find

Load balancer and autoscaling are the solutions that should be implemented to address the requirements of optimizing system capacity and reducing cost for an e-commerce site in the cloud. A load balancer is a device or service that distributes incoming network traffic across multiple servers or instances based on various criteria, such as availability, performance, or location. A load balancer can improve system capacity by balancing the workload and preventing overloading or underutilization of resources. Autoscaling is a feature that allows cloud services to automatically adjust the number of servers orinstances based on the demand or predefined rules. Autoscaling can reduce cost by scaling up or down the resources as needed, avoiding unnecessary expenses or wastage.

A risk associated with SDN is the expanded attack surface that it introduces. SDN is a network architecture that decouples the control plane from the data plane, allowing centralized and programmable management of network devices and traffic. However, this also exposes new attack vectors and vulnerabilities that can compromise the security and performance of the network. For example, an attacker can target the SDN controller, which is the core component that communicates with and controls the network devices. A successful attack on the SDN controller can result in denial of service, unauthorized access, data leakage, or network hijacking. An attacker can also exploit the communication channels between the SDN controller and the network devices, such as the OpenFlow protocol, to intercept, modify, or inject malicious messages or commands. Additionally, an attacker can leverage malicious or compromised applications that run on top of the SDN controller to manipulate or disrupt the network behavior. Verified References:

https://www.isaca.org/resources/isaca-journal/issues/2016/volume-4/benefits-and-the-security-risk-of-software-defined-networking

https://link.springer.com/article/10.1007/s40860-022-00171-8

Containerization is a technology that allows applications to run in isolated and portable environments called containers. Containers are lightweight and self-contained units that include all the dependencies, libraries, and configuration files needed for an application to run. Containers can be deployed on any platform that supports the container runtime engine, such as Docker or Kubernetes.

Containerization would allow the company to refactor a monolithic application to take advantage of cloud native services and service microsegmentation to secure sensitive application components, because containerization would:

Enable the application to be split into smaller and independent components (microservices) that can communicate with each other through APIs or message queues.

Allow the application to leverage cloud native services, such as load balancers, databases, or serverless functions, that can be integrated with containers through configuration files or environment variables.

Enhance the security of the application by isolating each container from other containers and the host system, and applying fine-grained access control policies and network rules to each container or group of containers.

Ensure the portability of the application by enabling it to run on any cloud provider or platform that supports containers, without requiring any changes to the application code or configuration.

Reviewing video from IP cameras within the facility would be the most likely process to expose an attacker who has compromised an air-gapped system. Since air-gapped systems are isolated from external networks, an attacker would need physical access to the system or use some covert channel to communicate with it. Video surveillance could reveal any unauthorized or suspicious activity within the facility that could be related to the attack. Verified References:

https://www.welivesecurity.com/wp-content/uploads/2021/12/eset_jumping_the_air_gap_wp.pdf

https://en.wikipedia.org/wiki/Air-Gap_Malware

https://www.techtarget.com/searchsecurity/essentialguide/How-air-gap-attacks-challenge-the-notion-of-secure-networks

MITRE ATT&CK is a threat management framework that provides a comprehensive and detailed knowledge base of adversary tactics and techniques based on real-world observations. It can help security analysts to identify, understand, and prioritize potential threats, as well as to develop effective detection and response strategies. MITRE ATT&CK covers the entire lifecycle of a cyberattack, from initial access to impact, and provides information on how to mitigate, detect, and hunt for each technique. It also includes threat actor profiles, software descriptions, and data sources that can be used for threat intelligence and analysis. MITRE ATT&CK is the most likely resource that a security analyst would adopt to implement the most up-to-date and effective security methodologies for their clients. Verified References:

https://attack.mitre.org/

https://resources.infosecinstitute.com/topic/top-threat-modeling-frameworks-stride-owasp-top-10-mitre-attck-framework/

Delivering an updated threat signature throughout the endpoint detection and response (EDR) system is the best way to take advantage of the security solution that uses a sandbox environment to execute zero-day software and collect indicators of compromise. An EDR system is a solution that monitors and analyzes the activities and behaviors of endpoints, such as computers, mobile devices, or servers, and detects and responds to potential threats. An EDR system can use threat signatures, which are patterns or characteristics of known malicious software or attacks, to identify and block malicious activities on endpoints. By delivering an updated threat signature based on the indicators ofcompromise collected from the sandbox environment, the organization can enhance its EDR system’s ability to detect and prevent zero-day attacks that exploit unknown vulnerabilities. Verified References:

https://www.cisco.com/c/en/us/products/security/what-is-endpoint-detection-response.html

https://www.crowdstrike.com/epp-101/what-is-a-sandbox/