Does anyone know what this is?

[zeropaid]

<script type="text/javascript" src="http://www.apiservicetracker.com/tracker.php"></script>

Was in the footer template. My initial thought is that we were hacked.

[emath]

this is not part of the default vbulletin for sure.

but are you sure you didnt try any tracker before ? especially if its in the footer, seems like someone did add this row manually.