How they get in is a problem, maybe SamuraiZero can help us find out more? Maybe on your end try to install chkrootkit or rkhunter to see if there are any vulnerabilities.
Just checked the cpanel backups on my old host and the xml file is there too. That host was hacked once, so if the problem is with the xml file, it might be the reason.
I sure will wisdomtool. Can somebody confirm that there is no problem with the remaining pages too. It is fine for me.
Well, the a few other sites on the same server have the same problem too, so I guess I wasted too much time on finding the flaws in my code.
You have been iFramed by the looks of things, you website has been targeted to exploit peoples browsers to potentially put the people on a botnet. if you need security against such things, send me a PM.
Complain to your host and have it fixed if you are not having a dedicated server nothing much you can do.
Google search on the subject says that it is a problem with the linux kernel that allows tha hacker to inject code into random files. I opened a support ticket with my host and they are working on it.