Using Blockchain to Protect Against Cyberattacks: Promising Practices and Future Directions Cybercriminals' prey isn't limited to the corporate world. The fact that nation-states have been successfully attacked online shows that cyber threats may endanger vital national interests. As a result, countries have launched what is called "cyber defence" at the national level to deal with cyber threats. The importance of the cyber defence industry to national security necessitates the use of cutting-edge security systems. Blockchain, in contrast to traditional systems, offers robust security qualities devoid of a centralised control body; as a result, it is receiving a lot of attention for its potential use in the cyber defence field. In this article, we discuss the benefits and drawbacks of using blockchain technology in cyber security, academic and government endeavours. We compiled a survey of material published between 2016 and 2021, including official documents, interviews, news articles, technical reports, and research papers. So, by methodically researching and analysing blockchain's potential for cyber protection, our work helps narrow the gap. According to our findings, blockchain is being aggressively promoted not just by academic institutions but also by government-led schemes, suggesting that it will have a significant impact on cybersecurity. Future research directions for blockchain technology, assessment, and survey are discussed in the last section of this work.