Suspicious Process Patterns NTDS.DIT Exfil — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2022-03-11 / 2022-11-10.

{
  "product": "windows",
  "category": "process_creation"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: ee87b516424a392320b758fdb48f4d0083d65c6a297bd1804bd99abeda27e682

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Suspicious Process Patterns NTDS.DIT Exfil
id: 8bc64091-6875-4881-aaf9-7bd25b5dda08
status: test
description: Detects suspicious process patterns used in NTDS.DIT exfiltration
references:
    - https://www.ired.team/offensive-security/credential-access-and-credential-dumping/ntds.dit-enumeration
    - https://www.n00py.io/2022/03/manipulating-user-passwords-without-mimikatz/
    - https://pentestlab.blog/tag/ntds-dit/
    - https://github.com/samratashok/nishang/blob/414ee1104526d7057f9adaeee196d91ae447283e/Gather/Copy-VSS.ps1
    - https://github.com/zcgonvh/NTDSDumpEx
    - https://github.com/rapid7/metasploit-framework/blob/d297adcebb5c1df6fe30b12ca79b161deb71571c/data/post/powershell/NTDSgrab.ps1
    - https://blog.talosintelligence.com/2022/08/recent-cyber-attack.html?m=1
author: Florian Roth (Nextron Systems)
date: 2022-03-11
modified: 2022-11-10
tags:
    - attack.credential-access
    - attack.t1003.003
logsource:
    product: windows
    category: process_creation
detection:
    selection_tool:
        # https://github.com/zcgonvh/NTDSDumpEx
        - Image|endswith:
              - '\NTDSDump.exe'
              - '\NTDSDumpEx.exe'
        - CommandLine|contains|all:
              # ntdsdumpex.exe -d ntds.dit -o hash.txt -s system.hiv
              - 'ntds.dit'
              - 'system.hiv'
        - CommandLine|contains: 'NTDSgrab.ps1'
    selection_oneliner_1:
        # powershell "ntdsutil.exe 'ac i ntds' 'ifm' 'create full c:\temp' q q"
        CommandLine|contains|all:
            - 'ac i ntds'
            - 'create full'
    selection_onliner_2:
        # cmd.exe /c copy z:\windows\ntds\ntds.dit c:\exfil\ntds.dit
        CommandLine|contains|all:
            - '/c copy '
            - '\windows\ntds\ntds.dit'
    selection_onliner_3:
        # ntdsutil "activate instance ntds" "ifm" "create full c:\windows\temp\data\" "quit" "quit"
        CommandLine|contains|all:
            - 'activate instance ntds'
            - 'create full'
    selection_powershell:
        CommandLine|contains|all:
            - 'powershell'
            - 'ntds.dit'
    set1_selection_ntds_dit:
        CommandLine|contains: 'ntds.dit'
    set1_selection_image_folder:
        - ParentImage|contains:
              - '\apache'
              - '\tomcat'
              - '\AppData\'
              - '\Temp\'
              - '\Public\'
              - '\PerfLogs\'
        - Image|contains:
              - '\apache'
              - '\tomcat'
              - '\AppData\'
              - '\Temp\'
              - '\Public\'
              - '\PerfLogs\'
    condition: 1 of selection* or all of set1*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://www.ired.team/offensive-security/credential-access-and-credential-dumping/ntds.dit-enumeration
• https://www.n00py.io/2022/03/manipulating-user-passwords-without-mimikatz/
• https://pentestlab.blog/tag/ntds-dit/
• https://github.com/samratashok/nishang/blob/414ee1104526d7057f9adaeee196d91ae447283e/Gather/Copy-VSS.ps1
• https://github.com/zcgonvh/NTDSDumpEx
• https://github.com/rapid7/metasploit-framework/blob/d297adcebb5c1df6fe30b12ca79b161deb71571c/data/post/powershell/NTDSgrab.ps1
• https://blog.talosintelligence.com/2022/08/recent-cyber-attack.html?m=1