Cyber-security is a fast-changing area of discussion due to advanced technologies that have given room for many cybercriminals and attacks in recent years. Cloud computing and increased levels of machine-to-machine interactions have created potential loopholes for invasion. Therefore, it is important to secure the user’s privacy, data, and devices in cyberspace. Recent years have seen tremendous change and increase in machine learning (ML) algorithms that are solving four main cyber-security issues, such as IDS, Android malware detection, spam detection, and malware analysis. The study analyzed these algorithms using a knowledge base system and data mining of information collected from various sources. The outcomes have shown that ML is an efficient way to address cyber-security risks.