This document summarizes an empirical study on cyber security threats and attacks. It discusses recent trends in cyber attacks such as ransomware, advanced persistent threats, insider threats, malware, and botnets. It also examines vulnerabilities in critical infrastructure that can be exploited by attackers. The document provides examples of research analyzing specific cyber threats and vulnerabilities. It concludes that understanding cyber threats is important for protecting systems and networks, and that security policies and monitoring are needed to mitigate threats and safeguard systems.