网站前不久有木马右下角跳出广告瑞星网站联盟也没有提示有木马呢?

网站http://www.57see.com/前几天遭黑客入侵,后台显示异常,显示Web攻击。后来网站上右下角偶尔跳出广告,瑞星联盟没有提示有木马,网页上没有发现挂马代码,广告有时一个小时会出现,没有规律,跳出广告的代码如下:
<div id="LELE_ShowDIV_UNIONtop" style="position: fixed; z-index: 2147483647; bottom: 0px; right: 0px; overflow: visible;"><div id="LELE_ShowDIV_UNION" style="position: fixed; z-index: 2147483647; bottom: 0px; right: 0px; overflow: hidden;"><div id="_33" style="z-index: 2147483648; cursor: pointer; top: 6px; left: 242px; width: 25px; height: 13px; display: block; position: absolute;"><img style="width:56px; height:23px;padding:0px;border:0px;" src="http://ad.daohang365.net:8089/99vjj/images/close.jpg"></div><div id="adfdiv" style="margin: 0px; padding: 0px; width: 300px; height: 250px;"><div style="position:absolute;z-index:1"></div>  <iframe id="adIframe" name="adIframe" src="http://www.gamegogo.net/?link=aHR0cDovL3d3dy5nYW1lZ29nby5uZXQvYWQvaHktZ20uaHRtbA==" height="250" width="300" scrolling="no" frameborder="0"> </iframe> </div></div><div id="LELE_ShowDIV_UNION_REPLAY" style="position: fixed; z-index: 2147483647; bottom: 0px; right: 0px; overflow: hidden; display: none;"><div style="z-index: 2147483646; cursor: pointer; bottom: 0px; right: 0px; width: 60px; height: 65px;"><img style="width:60px; height:65px;padding:0px;border:0px;" src="http://img.sp.cc/d/chongbo.png"></div></div></div>
现在我应该如何处理呢?

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