Cybersecurity pros say terror groups have little reason to launch a massive 9/11-scale cyberattack. Terrorists prefer to stay with physical attacks that attract a lot of attention, they say. Cyberattacks are inconsistent with the primary goal of most terrorist organizations, experts concur. Terror groups have adopted the internet as a way to communicate to like-minded followers, as well as spread propaganda, but that hasn’t crossed over into specific cyberthreats such as deploying ransomware or another type of malware. The attack would likely require a nation-state to conduct such an attack that would cause mass casualties.”]
Source: https://www.cuinfosecurity.com/20-years-later-cyber-911-unlikely-a-17477

