Detection rules › Splunk
Potential AutoHotkey .ahk Execution (Windows Event Log)
Adversaries may execute commands and perform malicious tasks using AutoIT and AutoHotKey automation scripts. AutoIT and AutoHotkey (AHK) are scripting languages that enable users to automate Windows tasks. These automation scripts can be used to perform a wide variety of actions, such as clicking on buttons, entering text, and opening and closing programs. This use case detects exeuction of .ahk files, accounting for renamed AutoHotkey binaries. Due to the broad nature of this rule, false positives for .ahk creation are expected. Allowlisting for expected executables and command line arguments is recommended.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution |
References
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Security-Auditing | Event ID 4688: A new process has been created. |
Rule body
id: '32266.57401'
title: Potential AutoHotkey .ahk Execution
description: Adversaries may execute commands and perform malicious tasks using AutoIT
and AutoHotKey automation scripts. AutoIT and AutoHotkey (AHK) are scripting languages
that enable users to automate Windows tasks. These automation scripts can be used
to perform a wide variety of actions, such as clicking on buttons, entering text,
and opening and closing programs. This use case detects exeuction of .ahk files,
accounting for renamed AutoHotkey binaries. Due to the broad nature of this rule,
false positives for .ahk creation are expected. Allowlisting for expected executables
and command line arguments is recommended.
logic_format: Splunk
logic: '`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR
"<EventID>4688<" OR Type=Process) ".ahk" | regex process="(?i)\.exe.+\S+\.ahk(\s|$|\")"
| table _time, host, user, process, parent_process_name, process_name, process_path
| bin span=1s | stats values(*) as * by _time, host '
techniques:
- execution:command and scripting interpreter
technique_id:
- T1059
data_category:
- Process command-line parameters
- Windows event logs
references:
- https://attack.mitre.org/techniques/T1059/010/
- https://detection.fyi/sigmahq/sigma/windows/process_creation/proc_creation_win_renamed_autohotkey/
- https://www.autohotkey.com/
Stages and Predicates
Stage 1: search
`get_endpoint_data` `get_endpoint_data_winevent` (TERM(EventCode=4688) OR "<EventID>4688<" OR Type=Process) ".ahk"
Stage 2: regex
| regex process="(?i)\.exe.+\S+\.ahk(\s|$|\")"
Stage 3: table
| table _time, host, user, process, parent_process_name, process_name, process_path
Stage 4: bucket
| bin span=1s
Stage 5: stats
| stats values(*) as * by _time, host
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
EventCode | eq |
| field:"EventID" kind:eq value:"4688" |
process | regex_match |
| field:"CommandLine" kind:regex_match |
Search terms
These SPL tokens match against raw event text.
| Stage | Term |
|---|---|
| 1 | "<EventID>4688<" |
| 1 | ".ahk" |