Crypto-Ransomware: A Revision of the State of the Art, Advances and Challenges

Abstract

According to the premise that the first step to try to solve a problem is to deepen our knowledge of it as much as possible, this work is mainly aimed at diving into and understanding crypto-ransomware, a very present and true-world digital pandemic, from several perspectives. With this aim, this work contributes the following: (a) a review of the fundamentals of this security threat, typologies and families, attack model and involved actors, as well as lifecycle stages; (b) an analysis of the evolution of ransomware in the past years, and the main milestones regarding the development of new variants and real cases that have occurred; (c) a study of the most relevant and current proposals that have appeared to fight against this scourge, as organized in the usual defence lines (prevention, detection, response and recovery); and (d) a discussion of the current trends in ransomware infection and development as well as the main challenges that necessarily need to be dealt with to reduce the impact of crypto-ransomware. All of this will help to better understand the situation and, based on this, will help to develop more adequate defence procedures and effective solutions and tools to defeat attacks.