detection.wiki

Detection rules › Splunk

Windows Hidden Schedule Task Settings

Status
production
Severity
medium
Group by
TaskContent, action, dest, signature, status, task_name
Author
Teoderick Contreras, Splunk
Source
github.com/splunk/security_content

The following analytic detects the creation of hidden scheduled tasks on Windows systems, which are not visible in the UI. It leverages Windows Security EventCode 4698 to identify tasks where the 'Hidden' setting is enabled. This behavior is significant as it may indicate malware activity, such as Industroyer2, or the use of living-off-the-land binaries (LOLBINs) to download additional payloads. If confirmed malicious, this activity could allow attackers to execute code stealthily, maintain persistence, or further compromise the system by downloading additional malicious payloads.

MITRE ATT&CK coverage

TacticTechniques
ExecutionT1053 Scheduled Task/Job
PersistenceT1053 Scheduled Task/Job
Privilege EscalationT1053 Scheduled Task/Job

Event coverage

ProviderEventTitle
Security-AuditingEvent ID 4698A scheduled task was created.

Rule body splunk

name: Windows Hidden Schedule Task Settings
id: 0b730470-5fe8-4b13-93a7-fe0ad014d0cc
version: 14
creation_date: '2022-04-27'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects the creation of hidden scheduled tasks on Windows systems, which are not visible in the UI. It leverages Windows Security EventCode 4698 to identify tasks where the 'Hidden' setting is enabled. This behavior is significant as it may indicate malware activity, such as Industroyer2, or the use of living-off-the-land binaries (LOLBINs) to download additional payloads. If confirmed malicious, this activity could allow attackers to execute code stealthily, maintain persistence, or further compromise the system by downloading additional malicious payloads.
data_source:
    - Windows Event Log Security 4698
search: |
    `wineventlog_security`
    EventCode=4698
    TaskContent = "*<Hidden>true</Hidden>*"
    | stats count min(_time) as firstTime max(_time) as lastTime
      by TaskName TaskContent action signature status dest
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_hidden_schedule_task_settings_filter`
how_to_implement: To successfully implement this search, you need to be ingesting logs with the task schedule (Exa. Security Log EventCode 4698) endpoints. Tune and filter known instances of Task schedule used in your environment.
known_false_positives: No false positives have been identified at this time.
references:
    - https://www.welivesecurity.com/2022/04/12/industroyer2-industroyer-reloaded/
    - https://cert.gov.ua/article/39518
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 ("$dest$") | 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: 7d
      latest_offset: "0"
finding:
    title: A schedule task with hidden setting enable in host $dest$
    entity:
        field: dest
        type: system
        score: 50
analytic_story:
    - CISA AA22-257A
    - Active Directory Discovery
    - Malicious Inno Setup Loader
    - Compromised Windows Host
    - Data Destruction
    - Industroyer2
    - Cactus Ransomware
    - Scheduled Tasks
    - Hellcat Ransomware
asset_type: Endpoint
mitre_attack_id:
    - T1053
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1053/hidden_schedule_task/inno_schtask.log
          source: XmlWinEventLog:Security
          sourcetype: XmlWinEventLog
      test_type: unit

Stages and Predicates

Stage 1: search

`wineventlog_security`
EventCode=4698
TaskContent = "*<Hidden>true</Hidden>*"

Stage 2: stats

| stats count min(_time) as firstTime max(_time) as lastTime
  by TaskName TaskContent action signature status dest

Stage 3: search

| `security_content_ctime(firstTime)`

Stage 4: search

| `security_content_ctime(lastTime)`

Stage 5: search

| `windows_hidden_schedule_task_settings_filter`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventCodeeq
  • 4698 corpus 14 (splunk 14)
TaskContenteq
  • "*<Hidden>true</Hidden>*"