Suspicious Process Patterns NTDS.DIT Exfil

Status: test
Severity: high
Log source: product windows, category process_creation
Author: Florian Roth (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects suspicious process patterns used in NTDS.DIT exfiltration

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1003.003` OS Credential Dumping: NTDS

Event coverage

Provider	Event	Title
Sysmon	Event ID 1	Process creation
Security-Auditing	Event ID 4688	A new process has been created.

Rule body yaml

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

Stages and Predicates

Stage 0: `condition`

1 of selection* or all of set1*

Stage 1: `selection_tool`

selection_tool:
    - Image|endswith:
          - '\NTDSDump.exe'
          - '\NTDSDumpEx.exe'
    - CommandLine|contains|all:
          - 'ntds.dit'
          - 'system.hiv'
    - CommandLine|contains: 'NTDSgrab.ps1'

Stage 2: `selection_oneliner_1`

selection_oneliner_1:
    CommandLine|contains|all:
        - 'ac i ntds'
        - 'create full'

Stage 3: `selection_onliner_2`

selection_onliner_2:
    CommandLine|contains|all:
        - '/c copy '
        - '\windows\ntds\ntds.dit'

Stage 4: `selection_onliner_3`

selection_onliner_3:
    CommandLine|contains|all:
        - 'activate instance ntds'
        - 'create full'

Stage 5: `selection_powershell`

selection_powershell:
    CommandLine|contains|all:
        - 'powershell'
        - 'ntds.dit'

Stage 6: `set1_selection_ntds_dit`

set1_selection_ntds_dit:
    CommandLine|contains: 'ntds.dit'

Stage 7: `set1_selection_image_folder`

set1_selection_image_folder:
    - ParentImage|contains:
          - '\apache'
          - '\tomcat'
          - '\AppData\'
          - '\Temp\'
          - '\Public\'
          - '\PerfLogs\'
    - Image|contains:
          - '\apache'
          - '\tomcat'
          - '\AppData\'
          - '\Temp\'
          - '\Public\'
          - '\PerfLogs\'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`CommandLine`	match	`/c copy` `NTDSgrab.ps1` `\windows\ntds\ntds.dit` corpus 5 (sigma 5) `ac i ntds` `activate instance ntds` `create full` `ntds.dit` corpus 2 (sigma 1, elastic 1) `powershell` corpus 25 (sigma 24, chronicle 1) `system.hiv`
`Image`	ends_with	`\NTDSDump.exe` `\NTDSDumpEx.exe`
`Image`	match	`\AppData\` corpus 7 (sigma 7) `\PerfLogs\` corpus 5 (sigma 5) `\Public\` corpus 2 (sigma 2) `\Temp\` corpus 4 (sigma 4) `\apache` `\tomcat`
`ParentImage`	match	`\AppData\` corpus 3 (sigma 3) `\PerfLogs\` corpus 2 (sigma 2) `\Public\` corpus 2 (sigma 2) `\Temp\` corpus 3 (sigma 3) `\apache` corpus 2 (sigma 2) `\tomcat` corpus 6 (sigma 6)

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

Suspicious Process Patterns NTDS.DIT Exfil

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection_tool`

Stage 2: `selection_oneliner_1`

Stage 3: `selection_onliner_2`

Stage 4: `selection_onliner_3`

Stage 5: `selection_powershell`

Stage 6: `set1_selection_ntds_dit`

Stage 7: `set1_selection_image_folder`

Indicators

Keyboard shortcuts

Search operators

Suspicious Process Patterns NTDS.DIT Exfil

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection_tool

Stage 2: selection_oneliner_1

Stage 3: selection_onliner_2

Stage 4: selection_onliner_3

Stage 5: selection_powershell

Stage 6: set1_selection_ntds_dit

Stage 7: set1_selection_image_folder

Indicators

Stage 0: `condition`

Stage 1: `selection_tool`

Stage 2: `selection_oneliner_1`

Stage 3: `selection_onliner_2`

Stage 4: `selection_onliner_3`

Stage 5: `selection_powershell`

Stage 6: `set1_selection_ntds_dit`

Stage 7: `set1_selection_image_folder`