Suspicious Scheduled Task Creation Involving Temp Folder — Sigma Rule

Rule metadata and linked tags

Author: Florian Roth (Nextron Systems). Source status: test; severity: high. Source dates: 2021-03-11 / 2022-10-09.

{
  "category": "process_creation",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: b89b0f16c8641b3c2f2ad4ad5d6571da14da3e5ebdf653663af38f1ee4ba932e

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 Involving Temp Folder
id: 39019a4e-317f-4ce3-ae63-309a8c6b53c5
status: test
description: Detects the creation of scheduled tasks that involves a temporary folder and runs only once
references:
    - https://discuss.elastic.co/t/detection-and-response-for-hafnium-activity/266289/3
author: Florian Roth (Nextron Systems)
date: 2021-03-11
modified: 2022-10-09
tags:
    - attack.privilege-escalation
    - attack.execution
    - attack.persistence
    - attack.t1053.005
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith: '\schtasks.exe'
        CommandLine|contains|all:
            - ' /create '
            - ' /sc once '
            - '\Temp\'
    condition: selection
falsepositives:
    - Administrative activity
    - Software installation
level: high

Original YAML and metadata in JSON

False positives

• Administrative activity
• Software installation

Source references

• https://discuss.elastic.co/t/detection-and-response-for-hafnium-activity/266289/3