about-hijacking.org


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What it's all about
Because of a Google-"feature", there is the possibility that under special conditions pages are heavily harmed by a 302 redirect or meta-refresh.

Whereat we explicitly want to point out, that in most cases of "Hijacking" we can't talk about a deliberate act, but rather ignorance.


How does it work?
Several web directories use a 302-redirect to link the listed pages. In doing so they don't use an ordinary link, but switch another page in-between to log exit pages, count clicks and similar. After that they redirect to the actual linked page. And at this point some of the redirect techniques can cause a "Hijacking".

problematical redirects:
HTML:<meta http-equiv="refresh" content="5; url=http://www.about-hijacking.org">
PHP: header("Location: http://www.example.com/");

In other languages like ASP there are similar possibilities to redirect. Also a redirect via .htaccess is possible.


What happens in a case of "Hijacking"?
Google sometimes assigns faulty the content of pages which are linked in that manner to the linking page. The exact conditions when it happens are not known to us.
So what can happen if a page is affected by this bug?
a) The linked page could be devaluated cause of duplicate content.
b) The linking page could get ranked better than the actual content owner page.
c) The linked page could get hijacked.

Remark on c:
Google removes the linked page from its index and replaces it by the "hijacking" page. Also the content of the linked page will be assigned to the "hijacking" page. At best it's just an unimportant sub page. In the worst case your root page is affected. In this case all sub pages will rank poorly or just completely disappear from the Google-Index. So the affected page won't get any visitors by Google which can cause serious economic damage.


How do I recognize if my page is "hijacked"?
By doing a Google search with "site:your-page.com" the "hijacking" page will be listed. Here, you should merely get pages from "your-page.com.

If the domain is affected by point c, you will find the "hijacking" page by searching for your domain name. Another symptom is that if you take a look at the Google cached version of the affected page, you will see the hijacking domain name instead of yours in the first line of the cached page. To view the cached version of a page , just conduct a Google search on "cache:http://www.your-page.com".


How can I protect my page getting hijacked?
Up to now there are no known techniques to prevent getting "hijacked". If your page is affected, just send a mail to the webmaster of the linking page and tell him to remove this kind of link.


I use 302 or meta-refresh links on my own page. What can I do to not harm anyone?
Just deny the access to the redirecting page for Google by your robots.txt or use a 301-redirect.

The robots.txt should look something like this:
User-Agent: Googlebot
Disallow: /subpage/link.php

More information about the robots.txt under: http://www.google.com/webmasters/faq.html#nocrawl


What is Google's position on that topic?
Despite of all attempts to get a serious answer from Google concerning this problem, so far all our inquiries have been answered by standard support mails or have been ignored.



Please follow “Check link” in the menu above to check the possible danger of a link.