Ghost links

Selected answers from the Dumb SEO Questions Facebook & G+ community.

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  K Neeraj Kayastha: Dear experts, yesterday for the first time happened a weird thing. I got an assignment to review and then do onpage SEO for a website. It is an legal consulting company's website.
  
  I added webmaster and analytics to the site last week. I got report for behaviour- pageviews and all the pages are 404 links and of porn sites such as www.xyz.com//pornbc.com or xyz.com//abc-porn.in
  
  I tried to find such links on site or sitemap but not found any. What are these links and how can I found them so that I get them removed. Is it something nasty done by website development and running company. They are actually providing in bulk for about 20USD annually per site.
  
  Thanks!
• 
  Ramesh Singh: you can submit disavow file with including these domains and check on your site if these pages exist on your site. I suggest either do the website crawling by screaming frog or xenu to see if is their any page still exist on the site. ;
• 
  K Neeraj Kayastha: I think disavow works for backlinks +Ramesh Singh​ +Jim Munro​
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  K Neeraj Kayastha: I think disavow works for backlinks +Ramesh Singh​ +Jim Munro​
• 
  Janna Maica Feliciano: Hi. I had slightly similar problem a year ago : Few new pages from our website were *magically created and all redirects to a foreign shopping site. The reason behind is caused by an injected malware.
  
  Try to check your .htaccess file and see if there's a suspicious new rule included within the file.
  
  If you think your site is infected with malwares, you may find some answers on Webmaster Tool Help:
  https://support.google.com/webmasters/answer/163634?hl=en
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  Ramesh Singh: +K Neeraj Kayastha ; If it is internally then try to search in Google with site:domain.com with words like porn this will give you pages indexed in Google and also do the internal site crawling using tools mentioned above. If these are started by certain words or folder block them via robots.txt and if these are indexed use URL removal from Google webmaster tools.
• 
  PromozSEO: site:domain.com may not show those links if the pages containing those links or words are not yet indexed by Google.
  Check if you have used any third-party plugins or code snippets recently. Some time these codes execute some javascript links which can make these types of problems.
  Make sure the site is not getting hacked test the database (if any). Check the common attacks, like SQL injection, XSS, CSRF etc.
  Sometimes cheap site-builders may add links on the fly which may not be found on the file itself.