This step is for sites hacked to host spam, often with the warning "This site may be hacked" displayed in search results. It's one of the longest steps in the recovery process. In this step, you'll compile a list of the damaged files on your site. You'll use this list in a later step, Clean and maintain your site.
Because certain hacking campaigns affect hundreds and thousands of sites in similar ways, they can be cleaned up using a set of specific steps. If any of these hacking campaigns describe the hack on your site, click through to read the guide.