With the increase in connectivity, the popularization of cloud services, and the rise of the Internet of Things (IoT), decentralized approaches for trust management are gaining momentum. Since blockchain technologies provide a distributed ledger, they are receiving massive attention from the research community in different application fields. However, this technology does not provide with cybersecurity by itself. Thus, this survey aims to provide with a comprehensive review of techniques and elements that have been proposed to achieve cybersecurity in blockchain-based systems. The analysis is intended to target area researchers, cybersecurity specialists and blockchain developers. For this purpose, we analyze 272 papers from 2013 to 2020 and 128 industrial applications. We summarize the lessons learned and identify several matters to foster further research in this area.
Keywords: Blockchain; Cybersecurity
Acknowledgments
The authors would like to thank the anonymous reviewers for their comments and suggestions, as well as Prof. Javier Lopez, Dr. David Galindo and Dr. David Nunez for their comments on the first stages of this paper.
This work has been partially funded by MINECO, Spain grantsTIN2016-79095-C2-2-R (SMOG-DEV) and PID2019-111429RB-C21 (ODIO-COW); by CAM, Spain grants S2013/ICE-3095 (CIBERDINE),P2018/TCS-4566 (CYNAMON), co-funded by European Structural Funds (ESF and FEDER); by UC3M-CAM grant CAVTIONS-CM-UC3M; by the Excellence Program for University Researchers, Spain; and by Consejo Superior de Investigaciones Científicas (CSIC), Spain under the project LINKA20216 (“Advancing in cybersecurity technologies”, i-LINK+ program).