Abstract
Conventionally, the security of critical infrastructures was mainly focused on environmental threats. Cyber attacks, nevertheless, have shifted the attention to various other threats and damages. The attackers try to exploit vulnerabilities in networks and Internet of Things (IoT) technologies, since these technologies are the integral part of the critical systems. Therefore, the vulnerability of Critical Infrastructure (CI) against cyber threats has led the need to devise modern security measures. Unavailability or failure of one CI can cause enormous devastation and damage to the society, economy and stability by provoking cascading failures to many other related infrastructures. Traditional security measures attempt to cater well-known emerging threats; however, strong and adaptive security measures/techniques are inevitable to defend against innovative attacks. This paper presents a survey on cyber threats and defense measures to highlight the necessity for securing SCADA-based critical infrastructures and provides an insight into the security challenges and open issues in this regard. (C) 2019 The Authors. Published by Elsevier B.V.