Detection: Windows Scheduled Task Created in a Group Policy Object

Updated Date: 2026-04-13 ID: 350032cd-3d3f-4278-afc8-e01cf5c33524 Author: Raven Tait, Splunk Type: TTP Product: Splunk Enterprise Security

Description

When a scheduled task is created within a Group Policy, a characteristic file ScheduledTasks.xml with its definition is created in the respective subfolder of the SYSVOL share. This rule can hit on legitimate GPO scheduled task creation, but this does not happen often and is therefore an effective way to monitor for malicious scheduled tasks.

Search

 1`wineventlog_security`
 2EventID=5145
 3ShareName="\\*\\SYSVOL"
 4RelativeTargetName="*\\ScheduledTasks\\ScheduledTasks.xml"
 5RelativeTargetName="*\\Policies\\*"
 6AccessList IN (
 7    "*%%4417*",
 8    "*%%4418*"
 9)
10
11| fillnull
12
13| stats count min(_time) as firstTime
14              max(_time) as lastTime
15  by Computer ShareName RelativeTargetName AccessList
16
17
18| rename Computer as dest
19
20| `security_content_ctime(firstTime)`
21
22| `security_content_ctime(lastTime)`
23
24| `windows_scheduled_task_created_in_a_group_policy_object_filter`

Data Source

Name	Platform	Sourcetype	Source
Windows Event Log Security 5145	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Security'`

Macros Used

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

windows_scheduled_task_created_in_a_group_policy_object_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
T1484.001	Group Policy Modification	Defense Impairment
T1053.005	Scheduled Task	Privilege Escalation

Exploitation

Installation

DE.CM

CIS 10

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 Notable	Yes
Rule Title	`%name%`
Rule Description	`%description%`
Notable Event Fields	user, dest
Creates Risk Event	True

This configuration file applies to all detections of type TTP. These detections will use Risk Based Alerting and generate Notable Events.

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

Some legitimate scheduled tasks are occasionally created via Group Policy Objects in managed environments. Filter alerts for approved GPO deployments to reduce false positives.

Associated Analytic Story

Risk Based Analytics (RBA)

Risk Message:

Potential Scheduled task created in a Group Policy Object activity observed on $dest$.

Risk Object	Risk Object Type	Risk Score	Threat Objects
dest	system	50	No Threat Objects

References

https://docs.microsoft.com/en-us/windows/security/threat-protection/auditing/event-5145

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Security`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Security`	`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: 1