Except Islamic Fundamentalists who believe in some Old man in the sky telling them to kill the unbelievers will never be that sophisticated.
Notice that NONE of the major cyberattacks done globally come from Islamic terror groups and only one Islamic nation has been implicated in cyber attacks:Iran, which does not blend well with sunni fundamentalist groups.The Syrian Electronic army is a secularist group
If there will be cyber attacks, they will be done by individuals or small groups rather than large ones and all of them will stem from groups that believe in a secular ideology.
Like how Estonia was unable to access the internet in 2007 because of Russia due to what is considered to be the second largest DDoS attack in internet history