Detection rules › Splunk

Symbolic OR Hard File Link Created (Windows Event Log)

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

Symbolic links are ways of referencing other files or programs that will be opened or executed when the shortcut is clicked or executed by a system startup process

MITRE ATT&CK coverage

References

Event coverage

Rule body yaml

id: '6105.6585'
title: Symbolic OR Hard File Link Created
description: 'Symbolic links are ways of referencing other files or programs that
  will be opened or executed when the shortcut is clicked or executed by a system
  startup process. -- Threat Actor Association: APT29/Nobelium, APT43, Arid Viper/APT
  C-23, Kimsuky, Lancefly, Gamaredon Group/Shuckworm,/Armageddon, SideWinder, TA505,
  TA576, UAC-0057 (GhostWriter), UNC2589, UNC4990, Wizard Spider -- Software Association:
  Astaroth, Black Basta, Bumblebee, Emotet, MINEBRIDGE, Qakbot/Qbot, Trickbot, Remcos
  RAT - #TrendingThreat #Russia #Ukraine - Atomics T1546.008 Test #3'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
  "<EventID>4688<" OR Type=Process) TERM(mklink) | table _time, host, user, process,
  process_*, parent_* | bin span=1s | stats values(*) as * by _time, host '
techniques:
- persistence:boot or logon autostart execution:shortcut modification
- privilege-escalation:boot or logon autostart execution:shortcut modification
- execution:user execution:malicious file
technique_id:
- T1547.009
- T1204.002
data_category:
- Windows event logs
- Process command-line parameters
references:
- https://blog-assets.f-secure.com/wp-content/uploads/2019/10/15163408/BlackEnergy_Quedagh.pdf
- https://www.fireeye.com/blog/threat-research/2019/01/apt39-iranian-cyber-espionage-group-focused-on-personal-information.html

Stages and Predicates

Stage 1: search

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

Stage 2: table

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

Stage 3: bucket

| bin span=1s

Stage 4: 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
  • 4688 corpus 313 (splunk 283, kusto 30)

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>4688<"
1TERM
1mklink