Convert batch script into base64 / non-readable format - batch-file

Question

Years ago I saw some batch scripts that contain nothing relevant at a fist look, but with a lot of content. The content was base64 encoded, and when you run the scripts, they are just running the commands that are encoded there.
Something like
SET mypath=%~dp0
echo "%mypath%
will look similar with
some_base_64_decoding_function(
U0VUIG15cGF0aD0lfmRwMA0KIGVjaG8gIiVteXBhdGgl
)
I don't really remember how those file were, and I can't find anything relevant on the Internet, except this article: Convert PowerShell script into non-readable format
but this only refeer to PowerShell scripts, and I need it for .bat scripts.
Anyone to give me a hint?

Answer 1

This is a sample batch file for encoding files in Base 64 with Certutil utility.
How to use it?
Just save this code on your notepad or on notepad++ or on any text editor as :
Certutil_B64_Encoding_Files.bat and drag and drop any file over it to be encoded
#echo off
Title Encoding files with CERTUTIL utility by Hackoo 2017
color 0A & Mode 83,3
If "%~1"=="" (
color 0C & Mode 80,3
echo(
echo You must drag and drop a file over this batch script to be encoded !
Timeout /T 5 /nobreak>nul & exit /b
)
#for /f %%i in ("certutil.exe") do if not exist "%%~$path:i" (
echo CertUtil.exe not found.
pause
exit /b
)
set "TempFile=%Temp%\Temp_b64
set "OutputFile=%~nx1_encoded%~x0"
If exist "%OutputFile%" Del "%OutputFile%" >nul 2>&1
echo(
echo Please wait a while ... Encoding "%~nx1" is in progress ...
certutil.exe -f -encode "%~1" "%TempFile%" >nul 2>&1
(
echo #echo off
echo CERTUTIL -f -decode "%%~f0" "%%Temp%%\%~nx1" ^>nul 2^>^&1
echo Start "%~n1" "%%Temp%%\%~nx1"
echo Exit
)>> "%OutputFile%"
copy "%OutputFile%" /b + "%TempFile%" /b >nul 2>&1
If exist "%TempFile%" Del "%TempFile%" >nul 2>&1
Timeout /T 2 /NoBreak>nul & exit
Encoded HTA Example: CommandLine.hta_encoded.bat
This is a result of an encoded output of a HTA file of mine named as CommandLine.hta_encoded.bat
So, you should copy and paste this code as CommandLine.hta_encoded.bat and execute it by double click. And you will get something like this :
Encoded VBS Example : DJBuzzRadio.vbs_encoded.bat
#echo off
CERTUTIL -f -decode "%~f0" "%Temp%\DJBuzzRadio.vbs" >nul 2>&1
Start "DJBuzzRadio" "%Temp%\DJBuzzRadio.vbs"
Exit
-----BEGIN CERTIFICATE-----
UGxheSAiaHR0cDovL3d3dy5jaG9jcmFkaW9zLmNoL2RqYnV6enJhZGlvX3dpbmRv
d3MubXAzLmFzeCINClN1YiBQbGF5KFVSTCkNCiAgIERpbSBTb3VuZA0KICAgU2V0
IFNvdW5kID0gQ3JlYXRlT2JqZWN0KCJXTVBsYXllci5PQ1giKQ0KICAgU291bmQu
VVJMID0gVVJMDQogICBTb3VuZC5zZXR0aW5ncy52b2x1bWUgPSAxMDANCiAgIFNv
dW5kLkNvbnRyb2xzLnBsYXkNCiAgIGRvIHdoaWxlIFNvdW5kLmN1cnJlbnRtZWRp
YS5kdXJhdGlvbiA9IDANCiAgICAgICB3c2NyaXB0LnNsZWVwIDEwMA0KICAgbG9v
cA0KICAgd3NjcmlwdC5zbGVlcCAoaW50KFNvdW5kLmN1cnJlbnRtZWRpYS5kdXJh
dGlvbikrMSkqMTAwMA0KRW5kIFN1Yg0K
-----END CERTIFICATE-----

Answer 2

MACRO-b64decode.bat
#echo off
SETLOCAL DISABLEDELAYEDEXPANSION
::DEFINITIONS
( set LF=^
%= EMPTY =%
)
set ^"NL=^^^%LF%%LF%^%LF%%LF%^^"
set $MACRO.ForEntireLine=^^^^^^^"eol^^^^=^^^^^^^%LF%%LF%^%LF%%LF%^^^%LF%%LF%^%LF%%LF%^^^^ delims^^^^=^^^^^^^"
::MACRO
ENDLOCAL &^
set $MACRO.b64exec=FOR %%? in (args main) do if "%%?" == "main" (%NL%
FOR %%a in (!args!) do (%NL%
^>encoded.txt echo %%a%NL%
^>nul certutil -decodehex encoded.txt decoded.txt 1%NL%
FOR /F %$MACRO.ForEntireLine% %%x in (decoded.txt) do %%x%NL%
del /F /Q encoded.txt decoded.txt%NL%
)%NL%
) ELSE SETLOCAL ENABLEDELAYEDEXPANSION ^& set args=
To call the macro inside your batch file:
call MACRO-b64decode.bat
%$MACRO.b64exec% ZWNobyBoZWxsbywgd29ybGReIQ==
which will output:
hello, world!
Note: DELAYEDEXPANSION is enabled