晚下服务器被攻击的，请高手给看看小弟我的文件，什么有关问题

晚上服务器被攻击的，请高手给看看我的文件，什么问题
今天晚上，我的服务器被黑了，屏幕如下图示，后面是我被修改的主页文件，请高手给看看，他怎么进来的，我的漏洞是什么？


index.php

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