I've been seeing some strange 404 activity in Wembaster Tools crawl error reports for the past few weeks. Google is somehow finding thousands of pages with prescription drug names in the the URL on the site I manage, but these pages don't actually exist, so they are 404ing. For example, www.domain.com/tramadol-with-oxycodone
Somebody must be pointing to them via links on one or more sites that Google is crawling. Unfortunately, Webmaster Tools isn't providing any data in the "Linked From" area of the crawl error report, so I have no idea where it's finding the pages. It only shows the detected and last crawled dates. I'm assuming the person creating these pages is doing it for one of the following reasons.
1: some type of negative SEO attempt on the specific site I manage
2. creating spam pages with junk content and links to try to optimize their pages for temporary SEO benefit
I've seen cases where sites have been hacked and thousands of actual pages have been added by the hacker, but I haven't come across any examples where someone would purposely link to non-existent pages.
Has anyone here come across this or a similar issue, and if so, do you have any recommendations on how to handle it? Google hasn't sent us any spam warnings, so I'm not overly concerned, just annoyed.
Thanks!
