Detection rules › Splunk

Registry Entry Created - PowerShell (PowerShell)

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

Adversaries may interact with the Windows Registry to hide configuration information within Registry keys, remove information as part of cleaning up, or as part of other techniques to aid in persistence and execution. This use case detects PowerShell scripts or commands creating new registry entries.

MITRE ATT&CK coverage

TacticTechniques
Persistence
Defense Impairment

References

Telemetry coverage

Rule body

id: '20185.35853'
title: Registry Entry Created - PowerShell
description: 'Adversaries may interact with the Windows Registry to hide configuration
  information within Registry keys, remove information as part of cleaning up, or
  as part of other techniques to aid in persistence and execution. This use case detects
  PowerShell scripts or commands creating new registry entries. '
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_powershell` ((EventCode=4104) OR "<EventID>4104<"
  OR (EventCode=4103) OR "<EventID>4103<") (TERM(New-Item) OR TERM(New-ItemProperty)
  OR TERM(Set-ItemProperty) OR TERM(sp) OR TERM(Set-Item) OR TERM(sip)) ("HKCU" OR
  "HKLM" OR "HKU" OR "HKEY_") | regex process="(?i)((New|Set)-Item(Property?)|sp|sip)\s+(-Path\s+?)(\"(HKCU|HKLM|HKU|HKEY_))"|
  table _time, host, user user, process, process_name | bin span=1s | stats values(*)
  as * by _time, host '
techniques:
- defense-evasion:modify registry
technique_id: 
- T1112
data_category:
- PowerShell logs
references:
- https://blog.sygnia.co/breaking-down-casbaneiro-infection-chain-part2?_ga=2.66949422.1638613298.1690290265-1923873697.1682517767
- https://gist.github.com/netbiosX/a114f8822eb20b115e33db55deee6692

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_powershell` ((EventCode=4104) OR "<EventID>4104<" OR (EventCode=4103) OR "<EventID>4103<") (TERM(New-Item) OR TERM(New-ItemProperty) OR TERM(Set-ItemProperty) OR TERM(sp) OR TERM(Set-Item) OR TERM(sip)) ("HKCU" OR "HKLM" OR "HKU" OR "HKEY_")

Stage 2: regex

| regex process="(?i)((New|Set)-Item(Property?)|sp|sip)\s+(-Path\s+?)(\"(HKCU|HKLM|HKU|HKEY_))"

Stage 3: table

| table _time, host, user user, process, process_name

Stage 4: bucket

| bin span=1s

Stage 5: stats

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

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
EventCodeeq
  • 4103 corpus 105 (splunk 105)
  • 4104 corpus 269 (splunk 269)
field:"EventID" kind:eq
processregex_match
  • "(?i)((New|Set)-Item(Property?)|sp|sip)\s+(-Path\s+?)(\"(HKCU|HKLM|HKU|HKEY_))"
field:"CommandLine" kind:regex_match

Search terms

These SPL tokens match against raw event text.

StageTerm
1"<EventID>4104<"
1"<EventID>4103<"
1"New-Item"
1"New-ItemProperty"
1"Set-ItemProperty"
1sp
1"Set-Item"
1sip
1"HKCU"
1"HKLM"
1"HKU"
1"HKEY_"