Detection rules › Splunk

Network Connection with Suspicious Folder (Windows Event Log)

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

Detects potential downloads to suspicious file locations like temp, appdata, and downloads

MITRE ATT&CK coverage

TacticTechniques
Command & ControlT1105 Ingress Tool Transfer

Event coverage

Rule body yaml

id: '9019.12103'
title: Network Connection with Suspicious Folder
description: 'Detects potential downloads to suspicious file locations like temp,
  appdata, and downloads. - Threat Actor Association: Alloy Taurus/Gallium, Lazarus,
  NewsPenguin, OilRig, TA413 - Software Association: LOWZERO, Vidar Stealer'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (EventCode=5156 OR "Event>ID<5156")
  ("Temporary Internet Files" OR TERM("TEMP") OR TERM("Downloads") OR TERM("Appdata"))
  | regex process_path="(?i)Temp|Downloads|Appdata" | table _time, host, user dest,
  direction, event_id, eventtype, parent_*, process, process_*, user, user_id, src_*,
  dest_* | bin span=1s | stats values(*) as * by _time, host, process_path '
techniques:
- command-and-control:ingress tool transfer
technique_id: 
- T1105
data_category:
- Windows event logs
references: null

Stages and Predicates

Stage 1: search

`get_endpoint_data` `get_endpoint_data_winevent` (EventCode=5156 OR "Event>ID<5156") ("Temporary Internet Files" OR TERM("TEMP") OR TERM("Downloads") OR TERM("Appdata"))

Stage 2: regex

| regex process_path="(?i)Temp|Downloads|Appdata"

Stage 3: table

| table _time, host, user dest, direction, event_id, eventtype, parent_*, process, process_*, user, user_id, src_*, dest_*

Stage 4: bucket

| bin span=1s

Stage 5: stats

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

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
  • 5156 corpus 15 (splunk 13, kusto 2)
process_pathregex_match
    • "(?i)Temp
    • Downloads
    • Appdata"
    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
1"Event>ID<5156"
1"Temporary Internet Files"
1"TEMP"
1"Downloads"
1"Appdata"