Detection rules › Splunk

Permission Groups Discovery: Local Groups (Sysmon)

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

Adversaries may attempt to find local system groups and permission settings. The knowledge of local system 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 the users found within the local administrators group

MITRE ATT&CK coverage

TacticTechniques
Discovery

References

Telemetry coverage

ProviderRecord / event type
SysmonEvent ID 1: Process creation

Rule body

id: '16743.26616'
title: 'Permission Groups Discovery: Local Groups'
description: 'Adversaries may attempt to find local system groups and permission settings.
  The knowledge of local system 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 the users
  found within the local administrators group. Atomics T1069.001 Test #3 Atomics T1069.001
  Test #5 Atomics T1069.001 Test #6'
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))) | table _time, host, user, process, process_*, parent_process
  | bin span=1s | stats values(*) as * by _time, host '
techniques:
- discovery:permission groups discovery
technique_id: 
- T1069
data_category:
- Windows Sysmon
- Process command-line parameters
references:
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1069.001/T1069.001.md#atomic-test-3---permission-groups-discovery-powershell-local

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: table

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

Stage 3: bucket

| bin span=1s

Stage 4: stats

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

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
EventCodeeq
  • 1 corpus 241 (splunk 225, kusto 15, elastic 1)
field:"EventID" kind:eq value:"1"

Search terms

These SPL tokens match against raw event text.

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