Hi,
I found that my website was hacked!
It starts on the HTML body with javascript function xViewState()
and follows with a lot of invisible spammy links wrapped with <p class="nemonn">. (can be seen only through view source)
The thing is - I found it on wordpress.org as well!!
I just removed it through the code editor so it doesn't appear anymore. If you google the line above you will find it on more websites built on wordpress, for example.
wordpress.org/support/topic/theme-meeta-how-to-remove-popular-posts-tags-in-header?replies=11
I have no idea when this code was injected. I have the latest version of wordpress, yet I have waited a bit before upgrading to it (couple of weeks)
Does anybody know what it is and how it got to the system?
Thanks in advance!
UPDATE: it seems not to be the first time. It was also reported on August 2012 for Joomla:
http://forum.joomla.org/viewtopic.php?f=621&t=754466