Detection: Short Lived Scheduled Task

Updated Date: 2026-07-07 ID: 6fa31414-546e-11ec-adfa-acde48001122 Author: Mauricio Velazco, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

The following analytic detects the creation and deletion of scheduled tasks within a short time frame (less than 30 seconds) using Windows Security EventCodes 4698 and 4699. This behavior is identified by analyzing Windows Security Event Logs and leveraging the Windows TA for parsing. Such activity may indicate lateral movement or remote code execution attempts by adversaries. If confirmed malicious, this could lead to unauthorized access, data exfiltration, or execution of malicious payloads, necessitating prompt investigation and response by security analysts.

Search

 1`wineventlog_security`
 2EventCode IN (4698, 4699)
 3
 4| xmlkv object_attrs
 5
 6| transaction TaskName dest startswith=(EventCode=4698) endswith=(EventCode=4699) maxspan=30s
 7
 8| stats count min(_time) AS firstTime
 9              max(_time) AS lastTime
10    by Command TaskName user dest RunLevel
11
12| `security_content_ctime(firstTime)`
13
14| `security_content_ctime(lastTime)`
15
16| `short_lived_scheduled_task_filter`

Data Source

Name	Platform	Sourcetype	Source
Windows Event Log Security 4698	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Security'`
Windows Event Log Security 4699	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Security'`

Macros Used

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

short_lived_scheduled_task_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
T1053.005	Scheduled Task	Execution

Exploitation

Installation

DE.AE

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 Finding (Notable)	No
Creates Intermediate Finding (Risk Event)	Yes

Anomaly detections generate Intermediate Findings (Risk Events). They do not generate a Finding (Notable) directly.

Implementation

To successfully implement this search, you need to be ingesting Windows Security Event Logs with 4698 EventCode enabled. The Windows TA is also required.

Known False Positives

Although uncommon, legitimate applications may create and delete a Scheduled Task within 30 seconds. Filter as needed.

Associated Analytic Story

Intermediate Findings

Message	Entity Field	Entity Type	Risk Score
A windows scheduled task [$TaskName$] with the command [$Command$] was created by [$user$] and deleted in less than 30 seconds on [$dest$]	dest	system	20

References

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: 12