Are blockchains immune to all malicious attacks?

Background: In recent years, blockchain technology has attracted considerable attention. It records cryptographic transactions in a public ledger that is difficult to alter and compromise because of the distributed consensus. As a result, blockchain is believed to resist fraud and hacking. Results: This work explores the types of fraud and malicious activities that can be prevented by blockchain technology and identifies attacks to which blockchain remains vulnerable. Conclusions: This study recommends appropriate defensive measures and calls for further research into the techniques for fighting malicious activities related to blockchains

Digital Currencies: Principles, Trends, Opportunities, and Risks

The report describes the ongoing innovations in the financial sector brought about by digital currencies from a multi-level perspective: systemic, technical, legal, and industrial. The report extensively covers the current trends in the domain, in order to give the reader a quantitative understanding of the potential opportunities and risks arising from the global adoption of digital currencies