Suspicious Scheduled Task Creation — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2022-12-05 / 2022-12-07.

{
  "product": "windows",
  "service": "security",
  "definition": "The Advanced Audit Policy setting Object Access > Audit Other Object Access Events has to be configured to allow this detection. We also recommend extracting the Command field from the embedded XML in the event data."
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 0351c4d3781057a81e1312fb947d27d18685b4683e6a4ff473e23b5a0df34888

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Suspicious Scheduled Task Creation
id: 3a734d25-df5c-4b99-8034-af1ddb5883a4
status: test
description: Detects suspicious scheduled task creation events. Based on attributes such as paths, commands line flags, etc.
references:
    - https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-10/security/threat-protection/auditing/event-4698
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-12-05
modified: 2022-12-07
tags:
    - attack.execution
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1053.005
logsource:
    product: windows
    service: security
    definition: 'The Advanced Audit Policy setting Object Access > Audit Other Object Access Events has to be configured to allow this detection. We also recommend extracting the Command field from the embedded XML in the event data.'
detection:
    selection_eid:
        EventID: 4698
    selection_paths:
        TaskContent|contains:
            - '\AppData\Local\Temp\'
            - '\AppData\Roaming\'
            - '\Users\Public\'
            - '\WINDOWS\Temp\'
            - 'C:\Temp\'
            - '\Desktop\'
            - '\Downloads\'
            - '\Temporary Internet'
            - 'C:\ProgramData\'
            - 'C:\Perflogs\'
    selection_commands:
        TaskContent|contains:
            - 'regsvr32'
            - 'rundll32'
            - 'cmd.exe</Command>'
            - 'cmd</Command>'
            - '<Arguments>/c '
            - '<Arguments>/k '
            - '<Arguments>/r '
            - 'powershell'
            - 'pwsh'
            - 'mshta'
            - 'wscript'
            - 'cscript'
            - 'certutil'
            - 'bitsadmin'
            - 'bash.exe'
            - 'bash '
            - 'scrcons'
            - 'wmic '
            - 'wmic.exe'
            - 'forfiles'
            - 'scriptrunner'
            - 'hh.exe'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high

Original YAML and metadata in JSON

False positives

• Unknown

Source references

• https://learn.microsoft.com/en-us/previous-versions/windows/it-pro/windows-10/security/threat-protection/auditing/event-4698