Detection rules › Splunk
AutoIt Execution (PowerShell)
AutoIt is a freeware scripting utility that can automate Windows GUI tasks such as mouse clicks, keystrokes, and window manipulations. While it is a legitimate tool, threat actors have abused it to automate malicious activity. This use case detects AutoIt, AutoIt2, or AutoIt3 executions, or commands loading .au3 files
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | T1059 Command and Scripting Interpreter |
References
Event coverage
| Provider | Event | Title |
|---|---|---|
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
Rule body yaml
id: '23090.41815'
title: AutoIt Execution
description: 'AutoIt is a freeware scripting utility that can automate Windows GUI
tasks such as mouse clicks, keystrokes, and window manipulations. While it is a
legitimate tool, threat actors have abused it to automate malicious activity. This
use case detects AutoIt, AutoIt2, or AutoIt3 executions, or commands loading .au3
files. -- Software Association: DarkGate'
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_powershell` (TERM(EventCode=4104) OR
"<EventID>4104<") ("AutoIT3.exe" OR "AutoIT2.exe" OR "AutoIT.exe" OR ".au3") | regex
process="(?i)\S+\.exe.+\.au3" | table _time, host, user, process, process_* | bin
span=1s | stats values(*) as * by _time, host '
techniques:
- execution:command and scripting interpreter
technique_id:
- T1059
data_category:
- PowerShell logs
references:
- https://isc.sans.edu/forums/diary/KPOT+Deployed+via+AutoIt+Script/25934/
- https://blog.talosintelligence.com/magnat-campaigns-use-malvertising-to/
- https://0xtoxin.github.io/threat%20breakdown/DarkGate-Camapign-Analysis/
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_powershell` (TERM(EventCode=4104) OR "<EventID>4104<") ("AutoIT3.exe" OR "AutoIT2.exe" OR "AutoIT.exe" OR ".au3")
Stage 2: regex
| regex process="(?i)\S+\.exe.+\.au3"
Stage 3: table
| table _time, host, user, process, process_*
Stage 4: bucket
| bin span=1s
Stage 5: 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.
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.
| Stage | Term |
|---|---|
| 1 | TERM |
| 1 | "<EventID>4104<" |
| 1 | "AutoIT3.exe" |
| 1 | "AutoIT2.exe" |
| 1 | "AutoIT.exe" |
| 1 | ".au3" |