A hacktivist is a type of actor who uses hacking techniques to promote a political or social cause or agenda. Hacktivists often target websites or systems of organizations or governments that they oppose or disagree with, and deface them with messages or propaganda related to their cause. In this case, the hacktivist defaced the corporate websites with political propaganda.

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

Creating a data minimization plan would be the most cost-effective solution to the current data privacy and protection gap found in the last security assessment. Data minimization is a principle that states that organizations should collect, store, process, and retain only the minimum amount of personal data that is necessary for their legitimate purposes. Data minimization can help reduce the risk of data breaches, data leaks, or data misuse by limiting the exposure and access to sensitive data. Data minimization can also help comply with data protection regulations, such as the General Data Protection Regulation (GDPR), that require organizations to justify their data collection and processing activities. Data minimization can be achieved by implementing various measures, such as deleting or anonymizing unnecessary data, applying retention policies, or using encryption or pseudonymization techniques.

To prevent adversaries from intercepting response and recovery details. Using a secure method of communication during incident response is important to prevent adversaries from intercepting response and recovery details that could reveal the incident response team's actions, strategies, or findings. If the adversaries can intercept the communication, they could use it to evade detection, escalate their privileges, or launch further attacks. To ensure intellectual property remains on company servers, to have a backup plan in case email access is disabled, or to ensure the management team has access to all the details that are being exchanged are other possible reasons to use a secure method of communication, but they are not as important as preventing adversaries from intercepting response and recovery details. Reference: https://www.sans.org/reading-room/whitepapers/incident/incident-handlers-handbook-33901

Nessus is a tool that would produce the assessment output needed to satisfy the request. Nessus is a vulnerability scanner that can scan a network or a system for known vulnerabilities and generate reports based on the findings. Nessus can also compare the vulnerabilities it finds with the Common Vulnerabilities and Exposures (CVE) database, which is a standardized list of publicly known security vulnerabilities and exposures2. Nessus can help identify hosts that have critical and high-severity findings as referenced in the CVE database.