Which of the following is a type of malware?

Ransomware is a type of malware that specifically targets and encrypts a victim's files, rendering them inaccessible unless a ransom is paid to the attacker. This malicious software takes advantage of vulnerabilities within systems to execute its payload and typically spreads through phishing emails, malicious downloads, or exploit kits. By compromising the data of individuals or organizations, ransomware poses a significant threat to cybersecurity, prompting the importance of understanding, detecting, and mitigating such malware.

In contrast, the other options represent security tools and policies rather than malware. Intrusion Detection Systems are designed to monitor networks for suspicious activity and potential threats, while security policies refer to the formalized rules and procedures that govern an organization’s security measures. Virtual Private Networks provide a secure connection over the internet, ensuring safe data transmission and privacy. Each of these plays a crucial role in network security but does not classify as malware.