Is my site hacked?

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

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  Girish Kapoor: Hello Guys, Please help me. I have faced 1 problem for my client website. When i checked cache (cache:http://www dot oasispalmdubai dot com) of my client website then it's showing some third party url in header.
  
  And also when i type client website url in google, then it's showing third party url in description section.
  
  I have already checked database files and header file of our website. But did not get anything clue till now. Please help me +Tim Capper ; +Jim Munro +Alistair Lattimore ;
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  Alistair Lattimore: Seems like a good candidate for a hacked site. Verify the site in Google Webmaster Tools and use the Fetch as Googlebot utility to see if you see that behaviour on any pages.
  
  Unrelated note, I'd recommend you address the massive bloat in the site home page as well -- for example there are four images each over 1MB in size the first of many issues to fix.
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  Toni Anicic: Check your .htaccess file. This looks like a hack that displays those links only when user agent is googlebot.
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  Girish Kapoor: Thanks +Alistair Lattimore i have already verify this website in Google Webmaster Tools. There is also showing as third party URL links when i click on Fetch as Google
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  Unipro Education Pvt. Ltd - Digital Marketing Agency: I have checked your website , the links are coming when you use http:// with your domain name while searching in google search box. You description might come from open directory projects use "meta noodp" to show your original descriptions.
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  Girish Kapoor: +Unipro Education Pvt. Ltd - Digital Marketing Agency thanks for your valuable suggestion but my website is not listed in Dmoz , then how it's possible to pick up description from open directory projects.
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  Toni Anicic: Girish, it's hacked. Once again, check your .htaccess file, or any other way that hacker could show different content on your website when a user agent is Googlebot. When you fix it, update your CMS and all of the plugins, change passwords.