Part A You Have Found That You Have 10 Systems In Your Netwo

Part A You Have Found That You Have 10 Systems In Your Network That A

You have discovered that there are ten systems within your network that are infected with malware and are part of a botnet. Among these systems, one is a web server, and the remaining nine are desktops used by various individuals and departments. Your task is to utilize your Incident Response Plan to manage and mitigate this situation effectively. Additionally, you need to outline preventive measures to prevent similar incidents in the future.

In responding to the infected systems, it is essential to follow a structured incident response process, which generally includes preparation, identification, containment, eradication, recovery, and lessons learned. First, thorough identification involves confirming the infection on each system through scanning and forensic analysis. Prioritize the web server, as its compromise could facilitate further attacks or data breaches, and then move onto the desktop systems.

Containment strategies should aim to prevent the spread of malware and botnet control commands. For the web server, this might involve isolating it from the network temporarily, disabling external access, and suspending any suspicious processes. For the desktop systems, similar steps include disconnecting them from the network, disabling network interfaces if necessary, and gathering forensic data for analysis.

Eradication involves removing malware from each system, which can include deleting malicious files, applying patches to vulnerabilities exploited by malware, and resetting affected systems to known clean states. In the case of the web server, ensure that any backdoors or vulnerabilities are addressed before redeployment. Before restoring systems to operational status, verify that all malware components are eliminated.

The recovery phase entails restoring systems to normal operations, implementing additional security measures, and monitoring for any signs of residual infection or re-infection. For the web server, this includes updating all software, configuring security features such as firewalls and intrusion detection systems, and restoring data from clean backups.

In terms of preventive measures for the future, you should implement comprehensive security controls. Regularly update and patch all systems and applications to close security vulnerabilities. Deploy robust antivirus and anti-malware solutions, and ensure they are always active and updated. Enhance network security through segmentation, intrusion detection systems, and firewalls. Educate users about security best practices, such as avoiding phishing attacks and suspicious downloads. Conduct periodic security audits and vulnerability assessments to identify and remediate weaknesses proactively. Establish a reliable incident response plan and conduct regular drills to ensure readiness in the event of future incidents.

Part B Complete Nmap Scans for Network Discovery and Security Assessment

To comprehensively assess the network segment (e.g., x.x.x.x/24), specific Nmap scans are required to identify active hosts, check for open ports, and determine possible operating systems and software versions. The first step is to perform a ping scan to identify live hosts within the segment, followed by a port scan to discover open ports on each device, and finally, an OS and service version scan for detailed system information.

For host discovery, an ICMP ping scan is suitable, which can be performed using:

nmap -sn x.x.x.x/24

This command sends ICMP echo requests to all addresses in the subnet, listing active hosts that respond. Note that some hosts may be configured to block ping requests, so no response does not necessarily mean the host is offline.

To perform a comprehensive port scan of all devices on the segment, revealing open ports and potential services, the following command is effective:

nmap -p- x.x.x.x/24

This scans all 65,535 TCP ports on each host, providing insights into running services that could be exploited. For an even more detailed understanding of the system's surface, including the operating system and specific software versions, an OS detection and service version scan should be performed:

nmap -sS -sV -O x.x.x.x/24

Here, '-sS' performs a stealth SYN scan, '-sV' retrieves service version information, and '-O' attempts to determine the operating system of each host. Combining these options generates a comprehensive profile of the network’s devices and their potential vulnerabilities.

It is crucial to conduct these scans responsibly and ethically, ensuring proper authorization before scanning a network segment, as unauthorized scanning can be illegal and may disrupt operations. These scans aid in identifying security weaknesses, which can then be prioritized for remediation to enhance network defenses.

References

• Gordon, S. (2019). Network Security Assessment: Know Your Network. O'Reilly Media.
• Harley, B. (2020). Mastering Nmap for Network Security: Scanning, Detection, and Pen Testing. Packt Publishing.
• Herbert, R., & McNabb, K. (2018). The Art of Network Penetration Testing. CRC Press.
• Nelson, J., Phillips, A., & Steuart, C. (2018). Guide to Computer Network Security. Springer.
• Scarfone, K., & Mell, P. (2007). Guide to Intrusion Detection and Prevention Systems (IDPS). NIST SP 800-94.
• Schneier, B. (2020). Click Here to Kill Everybody: Security and Survival in a Hyper-connected World. W. W. Norton & Company.
• Stallings, W., & Brown, L. (2018). Computer Security: Principles and Practice. Pearson.
• Symantec Corporation. (2020). Internet Security Threat Report. Symantec Corp.
• Whitman, M. E., & Mattord, H. J. (2019). Principles of Information Security. Cengage Learning.
• Zwicky, E. D., Cooper, S., & Chapman, D. B. (2000). Building Internet Firewalls. O'Reilly Media.