Detection: Windows Boot or Logon Autostart Execution In Startup Folder

Updated Date: 2024-09-30 ID: 99d157cb-923f-4a00-aee9-1f385412146f Author: Teoderick Contreras, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects the creation of files in the Windows %startup% folder, a common persistence technique. It leverages the Endpoint.Filesystem data model to identify file creation events in this specific directory. This activity is significant because adversaries often use the startup folder to ensure their malicious code executes automatically upon system boot or user logon. If confirmed malicious, this could allow attackers to maintain persistence on the host, potentially leading to further system compromise and unauthorized access to sensitive information.

Search

1
2|tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Filesystem where Filesystem.file_path = "*\\Microsoft\\Windows\\Start Menu\\Programs\\Startup\\*" by Filesystem.file_create_time Filesystem.process_id Filesystem.file_name Filesystem.user Filesystem.file_path Filesystem.process_guid Filesystem.dest 
3| `drop_dm_object_name(Filesystem)` 
4| `security_content_ctime(firstTime)` 
5| `security_content_ctime(lastTime)` 
6| `windows_boot_or_logon_autostart_execution_in_startup_folder_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 11	Windows	`'xmlwineventlog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`

Macros Used

Name	Value
security_content_ctime	`convert timeformat="%Y-%m-%dT%H:%M:%S" ctime($field$)`
windows_boot_or_logon_autostart_execution_in_startup_folder_filter	`search *`

windows_boot_or_logon_autostart_execution_in_startup_folder_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1547.001	Registry Run Keys / Startup Folder	Persistence
T1547	Boot or Logon Autostart Execution	Privilege Escalation

KillChainPhase.EXPLOITAITON

KillChainPhase.INSTALLATION

NistCategory.DE_AE

Cis18Value.CIS_10

APT18

APT19

APT28

APT29

APT3

APT32

APT33

APT37

APT39

APT41

BRONZE BUTLER

Cobalt Group

Confucius

Dark Caracal

Darkhotel

Dragonfly

FIN10

FIN13

FIN6

FIN7

Gamaredon Group

Gorgon Group

Higaisa

Inception

Ke3chang

Kimsuky

Lazarus Group

LazyScripter

Leviathan

LuminousMoth

Magic Hound

Molerats

Moonstone Sleet

MuddyWater

Mustang Panda

Naikon

PROMETHIUM

Patchwork

Putter Panda

RTM

RedCurl

Rocke

Sidewinder

Silence

TA2541

TeamTNT

Threat Group-3390

Tropic Trooper

Turla

Windshift

Wizard Spider

ZIRCONIUM

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Risk Event	True

This configuration file applies to all detections of type anomaly. These detections will use Risk Based Alerting.

Implementation

To successfully implement this search you need to be ingesting information on process that include the name of the Filesystem responsible for the changes from your endpoints into the Endpoint datamodel in the Filesystem node.

Known False Positives

Administrators may allow creation of script or exe in this path.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message	Risk Score	Impact	Confidence
a process dropped a file in %startup% folder in $dest$	81	90	90

The Risk Score is calculated by the following formula: Risk Score = (Impact * Confidence/100). Initial Confidence and Impact is set by the analytic author.

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub | Version: 3