If you need to copy a file but don’t want the data contained to be easily read and encryption/3rd party applications aren’t available, this PowerShell solution may help.
Here I have a file with some data I would like to obfuscate.
Below is the PowerShell steps which:
- Prepares some variable to point to the 1.txt file and other files which do not exist
- Here we simply convert the text file to Base64 so it is unreadable to humans and create a file called obfuscatedwithaddeddata
- We add a salt of 6 (this could be anything and anywhere in the file, but used here for simplicity) to the end of the file text. This essentially corrupts the file.
- Here is an attempt to try convert from Base64 to text and it will fail
- Here we remove the 6 (salt removed) and save it as a file called obfuscatedwithoutaddeddata
- Finally we can convert the file obfuscatedwithoutaddeddata to file called 2.txt
All these files were created here so you can review the contents through the process.
#1. files
$source_file = “C:\temp\obfuscate\1.txt”
$obfuscated_file = “C:\temp\obfuscate\obfuscatedwithaddeddata”
$unobfuscated_file = “C:\temp\obfuscate\obfuscatedwithoutaddeddata”
$dest_file = “C:\temp\obfuscate\2.txt”
#2. text -> Base64
[io.file]::WriteAllText($obfuscated_file, [Convert]::ToBase64String([io.file]::ReadAllBytes($source_file)))
#3. obfuscate by adding 6 to end of file
Add-Content -Path $obfuscated_file -Value 6
#4. attempt to reverse
# Base64 -> text
[io.file]::WriteAllBytes($dest_file, [System.Convert]::FromBase64String([io.file]::ReadAllText($obfuscated_file)))
#5. remove 6
$unobfuscated_data = Get-Content $obfuscated_file
$unobfuscated_data = $unobfuscated_data.Substring(0,$unobfuscated_data.Length-1)
Set-Content -Path $unobfuscated_file -Value $unobfuscated_data
#6. Base64 -> text
[io.file]::WriteAllBytes($dest_file, [System.Convert]::FromBase64String([io.file]::ReadAllText($unobfuscated_file)))
