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aGerman wrote:First of all thank you for using "obfuscate" instead of "encode" or "encrypt". Any attempt to securely use a password in a batch code is doomed to failure!
Obfuscated or not - somewhere in your code you will have a line like that:
if [input]==[password] ([success]) else [error]
It doesnt matter if you might have your password obfuscated or if you might have used a hash instead or if you might have read the password from a remote file. All you have to do is to remove the comparison from the batch code.

There are already dozens of possibilities using variables to obfuscate batch code. There are those bat2exe thingies that compress the code in a container (but will unpack it to the original code and execute it).

That's another funny possibility. It doesn't even obfuscate the code. It only confuses your editor if you try to open the batch file

Code: Select all

@echo off
if "%~1"=="" exit /b
if /i "%~x1" neq ".bat" if /i "%~x1" neq ".cmd" exit /b
for /f %%i in ("certutil.exe") do if not exist "%%~$path:i" (
  echo CertUtil.exe not found.
  pause
  exit /b
)
>"temp.~b64" echo(//4mY2xzDQo=
certutil.exe -f -decode "temp.~b64" "%~n1___%~x1"
del "temp.~b64"
copy "%~n1___%~x1" /b + "%~1" /b

Drag/drop your file to it. It creates a new batch file with 3 underscores appended to the name. Try to open it in a text editor. You should see any kind of Chinese characters.
If you open it in a HEX editor you'll see how it works - it prepends an FF FE Byte Order Mark (that leads to parse the code as UTF-16 LE in a text editor) + CLS to remove the error message that cmd.exe will throw.

Steffen

Hackoo wrote:I like this method
I wonder how we can get back the original batch file by programming ?

@echo off &setlocal
if "%~1"=="" exit /b
if /i "%~x1" neq ".bat" if /i "%~x1" neq ".cmd" exit /b
<"%~1" ((for /l %%N in (1 1 8) do pause)>nul&findstr "^">"%~n1___%~x1")

Hackoo wrote:Is there any methods like this one to do for *.vbs or *.hta codes
Thank you !

aGerman wrote:Any attempt to securely use a password in a batch code is doomed to failure!
Obfuscated or not - somewhere in your code you will have a line like that:
if [input]==[password] ([success]) else [error]
It doesnt matter if you might have your password obfuscated or if you might have used a hash instead or if you might have read the password from a remote file. All you have to do is to remove the comparison from the batch code.

@echo off
setlocal enableExtensions enableDelayedExpansion
call :main
goto :eof

:access
echo(Login or password incorrect.
goto :eof

:main
set /P "login=Login   :"
set /P "password=Password:"

call :computeHash login
>>"%~f0" call :decrypt hash password
call :access
copy /a "%~f0" /a "dummy"
copy /a "dummy" /a  "%~f0"
del "dummy"
goto :eof

:computeHash
:: "%~1" value
:: "%~2" hash
...

:decrypt
:: "%~1" database entry
:: "%~2" key
echo(EOF-character
echo(deccrypted database antry
goto :eof

:: database

#hash(login1)
:: encrypted batch source using key: password1
:: maybe encoded in base64, or similar

:: ...

#hash(loginN)
:: encrypted batch source using key: passwordN

aGerman wrote:

Hackoo wrote:I like this method
I wonder how we can get back the original batch file by programming ?

The prepended line in a HEX editor is
FF FE 26 63 6C 73 0D 0A
As you can see it's 8 characters. Just let PAUSE eat them.

Code: Select all

@echo off &setlocal
if "%~1"=="" exit /b
if /i "%~x1" neq ".bat" if /i "%~x1" neq ".cmd" exit /b
<"%~1" ((for /l %%N in (1 1 8) do pause)>nul&findstr "^">"%~n1___%~x1")

Again drag/drop the changed batch file onto it.
Steffen

aGerman wrote:@Hackoo
Works for me on Win7 x64. Make sure your batch file doesn't have the same name as any of the used commands. If that isn't the case please give a short explanation how to reproduce the failure.
Steffen

@echo off
if "%~1"=="" exit /b
if /i "%~x1" neq ".bat" if /i "%~x1" neq ".cmd" exit /b
if exist "%~n1___%~x1" del "%~n1___%~x1"
for /f "skip=1 delims=" %%L in ('CMD /U /C Type "%~1"') do (
   echo %%L
   echo %%L >>"%~n1___%~x1"
)
pause>nul