01. SEO Failure
Once the initial web attack is successful, the hacker will spread malware on the server. Once the webserver is infected with malware, it will be used as a zombie for a full-fledge DDoS attack. On top of that, malware will be spread to the visitors of your website.
At this point, Google will block your website that is infiltrated with malware and your search rankings will crash, resulting in SEO failure.