Detection rules › Splunk

Permission Groups Discovery: Domain Groups (Sysmon)

Group by
_time, host
Source
github.com/anvilogic-forge/armory

Adversaries may attempt to find domain-level groups and permission settings. The knowledge of domain-level permission groups can help adversaries determine which groups exist and which users belong to a particular group. Adversaries may use this information to determine which users have elevated permissions, such as domain administrators

MITRE ATT&CK coverage

References

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

id: '16633.25780'
title: 'Permission Groups Discovery: Domain Groups'
description: 'Adversaries may attempt to find domain-level groups and permission settings.
  The knowledge of domain-level permission groups can help adversaries determine which
  groups exist and which users belong to a particular group. Adversaries may use this
  information to determine which users have elevated permissions, such as domain administrators.
  -- Threat Actor Association: Mustang Panda (aka. Stately Taurus//Earth Preta/BRONZE
  PRESIDENT/TA416/RedDelta) - Software Association: Akira, Rhysida -- Atomics T1069.001
  Test #2 Atomics T1069.002 Test #1 Atomics T1069.002 Test #2 Atomics T1069.002 Test
  #3 Atomics T1069.002 Test #9 Atomics T1069.002 Test #10'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_sysmon` (TERM(EventCode=1) OR "<EventID>1<")
  TERM(Get-LocalGroup) OR TERM(Get-LocalGroupMember) OR (("wmic" OR TERM(Get-WMIObject)
  AND TERM(group))) | regex process="(?i)\s+(localgroup|group(s?)\s+.*doma)|Get-AD(PrincipalGroupMembership|Group)|objectcategory=group"
  | table _time, host, user, process, process_*, parent_process* | bin span=1s | stats
  values(*) as * by _time, host '
techniques:
- discovery:permission groups discovery:domain groups
- discovery:permission groups discovery
technique_id:
- T1069.002
- T1069
data_category:
- Windows Sysmon
- Process command-line parameters
references:
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1069.002/T1069.002.md#atomic-test-1---basic-permission-groups-discovery-windows-domain
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1069.002/T1069.002.md#atomic-test-2---permission-groups-discovery-powershell-domain
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1069.002/T1069.002.md#atomic-test-3---elevated-group-enumeration-using-net-group-domain

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_sysmon` (TERM(EventCode=1) OR "<EventID>1<") TERM(Get-LocalGroup) OR TERM(Get-LocalGroupMember) OR (("wmic" OR TERM(Get-WMIObject) AND TERM(group)))

Stage 2: regex

| regex process="(?i)\s+(localgroup|group(s?)\s+.*doma)|Get-AD(PrincipalGroupMembership|Group)|objectcategory=group"

Stage 3: table

| table _time, host, user, process, process_*, parent_process*

Stage 4: bucket

| bin span=1s

Stage 5: stats

| stats values(*) as * by _time, host

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.

FieldKindValues
EventCodeeq
  • 1 corpus 237 (splunk 224, kusto 13)
processregex_match
    • "(?i)\s+(localgroup|group(s?)\s+.*doma)
    • Get-AD(PrincipalGroupMembership|Group)
    • objectcategory=group"
    corpus 3 (splunk 3)

Search terms

Bare-string tokens in the SPL search body. Splunk matches each token against _raw (the untyped raw event text) anywhere it appears, not against a specific field. These don't surface in the Indicators table because they aren't predicates on a known field.

StageTerm
1TERM
1"<EventID>1<"
1"Get-LocalGroup"
1"Get-LocalGroupMember"
1"wmic"
1"Get-WMIObject"
1TERM
1group