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splunk-security_content/detections/endpoint/disable_schedule_task.yml

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YAML

name: Disable Schedule Task
id: db596056-3019-11ec-a9ff-acde48001122
version: 7
date: '2025-05-02'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects the execution of a command to disable
an existing scheduled task using 'schtasks.exe' with the '/change' and '/disable'
parameters. This detection leverages data from Endpoint Detection and Response (EDR)
agents, focusing on process names and command-line arguments. Disabling scheduled
tasks is significant as it is a common tactic used by adversaries, including malware
like IcedID, to disable security applications and evade detection. If confirmed
malicious, this activity could allow attackers to persist undetected, disable critical
security defenses, and further compromise the targeted host.
data_source:
- Sysmon EventID 1
- Windows Event Log Security 4688
- CrowdStrike ProcessRollup2
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime
max(_time) as lastTime from datamodel=Endpoint.Processes where Processes.process_name=schtasks.exe
Processes.process=*/change* Processes.process=*/disable* by Processes.action Processes.dest
Processes.original_file_name Processes.parent_process Processes.parent_process_exec
Processes.parent_process_guid Processes.parent_process_id Processes.parent_process_name
Processes.parent_process_path Processes.process Processes.process_exec Processes.process_guid
Processes.process_hash Processes.process_id Processes.process_integrity_level Processes.process_name
Processes.process_path Processes.user Processes.user_id Processes.vendor_product
| `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
| `disable_schedule_task_filter`'
how_to_implement: 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: admin may disable problematic schedule task
references:
- https://thedfirreport.com/2021/10/18/icedid-to-xinglocker-ransomware-in-24-hours/
drilldown_searches:
- name: View the detection results for - "$dest$"
search: '%original_detection_search% | search dest = "$dest$"'
earliest_offset: $info_min_time$
latest_offset: $info_max_time$
- name: View risk events for the last 7 days for - "$dest$"
search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$")
starthoursago=168 | stats count min(_time) as firstTime max(_time) as lastTime
values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories)
as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic)
as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`'
earliest_offset: $info_min_time$
latest_offset: $info_max_time$
rba:
message: schtask process with commandline $process$ to disable schedule task in
$dest$
risk_objects:
- field: dest
type: system
score: 56
threat_objects: []
tags:
analytic_story:
- IcedID
- Living Off The Land
asset_type: Endpoint
mitre_attack_id:
- T1562.001
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/malware/icedid/disable_schtask/sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: XmlWinEventLog