Probably not. I`ve come across several similar experiences from friends who have phoned me in a panic. There are websites out there that do this and it looks similar to a real attack on the machine. In reality the webpage is trying to legitimately (Or otherwise) get you to try a piece of AV software or malware remover but the script on the page is so similar to something malevolent that your own security software kicks in to disable it.
iMac Pro review