how do i get rid of cloudfront malware on iphone 8+ running ios 11.3.6?

Ok. Maybe I’ve used the wrong term. My phone is not jail broken. Lately I’ve had issues where I go to a website (macrumors was one recently) and safari gets hijacked and won’t let me back out of their instant amazon winner scam. I have to quit safari, remove anything in web site data that has “Cloudfront” in it and then avoid the websit I was trying to view. Any thoughts?