Abstract

Although the first hype of blockchains is over, subject matter experts are still convinced, that this technology has potential to enable more groundbreaking innovations in multiple business domains. However, to develop the full potential of this emerging technology, it is necessary to consider and address the associated risks. This survey aims at supporting researchers and practitioners to design, implement and improve their blockchain security and resilience by providing a concise overview on the subject. In this article, we describe 24 risks, which we structured into the four domains “Blockchain Structure Vulnerabilities”, “Attacks on the Consensus Mechanism”, “Application Oriented Attacks” and “Attacks on the Peer-to-Peer System”. For each entry, we outline a precise description of the vulnerability or attack, the complexity and its prerequisites.