Fsutil fsinfo execution (Windows Event Log)

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

Adversaries may attempt to gather information about attached peripheral devices and components connected to a computer system. Peripheral devices could include auxiliary resources that support a variety of functionalities such as keyboards, printers, cameras, smart card readers, or removable storage. This use case looks for when fsutil is executed with fsinfo

MITRE ATT&CK coverage

Tactic	Techniques
Discovery	`T1120` Peripheral Device Discovery

References

https://www.welivesecurity.com/wp-content/uploads/2020/05/ESET_Turla_ComRAT.pdf

Telemetry coverage

Provider	Record / event type
Security-Auditing	Event ID 4688: A new process has been created.

Rule body

id: '8150.10002'
title: Fsutil fsinfo execution
description: 'Adversaries may attempt to gather information about attached peripheral
  devices and components connected to a computer system. Peripheral devices could
  include auxiliary resources that support a variety of functionalities such as keyboards,
  printers, cameras, smart card readers, or removable storage. This use case looks
  for when fsutil is executed with fsinfo. - Threat Actor Association: APT29/Nobelium/Cozy
  Bear - Software Association: Alphv/BlackCat'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
  "<EventID>4688<" OR Type=Process) "fsutil" TERM(fsinfo) | table _time, host, user
  process, process_*, signature_id, parent_* | bin span=1s | stats values(*) as *
  by _time, host '
techniques:
- discovery:peripheral device discovery
technique_id: 
- T1120
data_category:
- Windows event logs
- Process command-line parameters
references:
- https://www.welivesecurity.com/wp-content/uploads/2020/05/ESET_Turla_ComRAT.pdf

Stages and Predicates

Stage 1: `search`

`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) "fsutil" TERM(fsinfo)

Stage 2: `table`

| table _time, host, user process, process_*, signature_id, parent_*

Stage 3: `bucket`

| bin span=1s

Stage 4: `stats`

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

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`EventCode`	eq	`4688` corpus 317 (splunk 283, kusto 33, elastic 1)	`field:"EventID" kind:eq value:"4688"`

Search terms

These SPL tokens match against raw event text.

Stage	Term
1	`"<EventID>4688<"`
1	`"fsutil"`
1	`fsinfo`