Get-ADUser Enumeration Using UserAccountControl Flags

Detects AS-REP roasting is an attack that is often-overlooked. It is not very common as you have to explicitly set accounts that do not require pre-authentication.

title: Get-ADUser Enumeration Using UserAccountControl Flags
id: 96c982fe-3d08-4df4-bed2-eb14e02f21c8
status: test
description: Detects AS-REP roasting is an attack that is often-overlooked. It is not very common as you have to explicitly set accounts that do not require pre-authentication.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1069.002/T1069.002.md#atomic-test-11---get-aduser-enumeration-using-useraccountcontrol-flags-as-rep-roasting
    - https://shellgeek.com/useraccountcontrol-flags-to-manipulate-properties/
author: frack113
date: 2022-03-17
tags:
    - attack.discovery
    - attack.t1033
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection:
        # 4194304 DONT_REQ_PREAUTH
        ScriptBlockText|contains|all:
            - 'Get-ADUser'
            - '-Filter'
            - 'useraccountcontrol'
            - '-band'
            - '4194304'
    condition: selection
falsepositives:
    - Legitimate PowerShell scripts
level: medium
regression_tests_path: regression_data/rules/windows/powershell/powershell_script/posh_ps_as_rep_roasting/info.yml

• T1033System Owner/User Discovery

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1069.002/T1069.002.md#atomic-test-11---get-aduser-enumeration-using-useraccountcontrol-flags-as-rep-roasting↗
• https://shellgeek.com/useraccountcontrol-flags-to-manipulate-properties/↗