T1022.md

T1022 - Data Encrypted

Description from ATT&CK

Data is encrypted before being exfiltrated in order to hide the information that is being exfiltrated from detection or to make the exfiltration less conspicuous upon inspection by a defender. The encryption is performed by a utility, programming library, or custom algorithm on the data itself and is considered separate from any encryption performed by the command and control or file transfer protocol. Common file archive formats that can encrypt files are RAR and zip.

Other exfiltration techniques likely apply as well to transfer the information out of the network, such as Exfiltration Over Command and Control Channel and Exfiltration Over Alternative Protocol

Atomic Tests

• Atomic Test #1 - Data Encrypted with zip and gpg symmetric

• Atomic Test #2 - Compress Data and lock with password for Exfiltration with winrar

• Atomic Test #3 - Compress Data and lock with password for Exfiltration with winzip

• Atomic Test #4 - Compress Data and lock with password for Exfiltration with 7zip

Atomic Test #1 - Data Encrypted with zip and gpg symmetric

Encrypt data for exiltration

Supported Platforms: macOS, Linux

Attack Commands: Run with sh!

mkdir /tmp/victim-files
cd /tmp/victim-files
touch a b c d e f g
echo "creating zip with password 'insert password here'"
zip --password "insert password here" ./victim-files.zip ./*
echo "encrypting file with gpg, you will need to provide a password"
gpg -c /tmp/victim-files/victim-filex.zip
#<enter passphrase and confirm>
ls -l

Cleanup Commands:

rm -Rf /tmp/victim-files

Atomic Test #2 - Compress Data and lock with password for Exfiltration with winrar

Note: Requires winrar installation rar a -p"blue" hello.rar (VARIANT)

Supported Platforms: Windows

Attack Commands: Run with command_prompt!

mkdir .\tmp\victim-files
cd .\tmp\victim-files
echo "This file will be encrypted" > .\encrypted_file.txt
rar a -hp"blue" hello.rar
dir

Atomic Test #3 - Compress Data and lock with password for Exfiltration with winzip

Note: Requires winzip installation wzzip sample.zip -s"blueblue" *.txt (VARIANT)

Supported Platforms: Windows

Inputs:

Name	Description	Type	Default Value
winzip_exe	Path to installed Winzip executable	Path	%ProgramFiles%\WinZip\winzip64.exe
winzip_url	Path to download Windows Credential Editor zip file	url	https://download.winzip.com/gl/nkln/winzip24-home.exe
winzip_hash	File hash of the Windows Credential Editor zip file	String	B59DB592B924E963C21DA8709417AC0504F6158CFCB12FE5536F4A0E0D57D7FB

Attack Commands: Run with command_prompt!

path=%path%;"C:\Program Files (x86)\winzip"
mkdir .\tmp\victim-files
cd .\tmp\victim-files
echo "This file will be encrypted" > .\encrypted_file.txt
"#{winzip_exe}" -min -a -s"hello" archive.zip *
dir

Dependencies: Run with powershell!

Description: Winzip must be installed

Check Prereq Commands:

cmd /c 'if not exist "#{winzip_exe}" (echo 1) else (echo 0)' 

Get Prereq Commands:

if(Invoke-WebRequestVerifyHash "#{winzip_url}" "$env:Temp\winzip.exe" #{winzip_hash}){
  Write-Host Follow the installation prompts to continue
  cmd /c "$env:Temp\winzip.exe"
}

Atomic Test #4 - Compress Data and lock with password for Exfiltration with 7zip

Note: Requires 7zip installation

Supported Platforms: Windows

Attack Commands: Run with command_prompt!

mkdir $PathToAtomicsFolder\T1022\victim-files
cd $PathToAtomicsFolder\T1022\victim-files
echo "This file will be encrypted" > .\encrypted_file.txt
7z a archive.7z -pblue
dir