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splunk-security_content/detections/endpoint/office_document_creating_schedule_task.yml
2023-09-20 16:22:08 -07:00

75 lines
3.2 KiB
YAML

name: Office Document Creating Schedule Task
id: cc8b7b74-9d0f-11eb-8342-acde48001122
version: 4
date: '2023-02-15'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: this search detects a potential malicious office document that create
schedule task entry through macro VBA api or through loading taskschd.dll. This
technique was seen in so many malicious macro malware that create persistence ,
beaconing using task schedule malware entry The search will return the first time
and last time the task was registered, as well as the `Command` to be executed,
`Task Name`, `Author`, `Enabled`, and whether it is `Hidden` or not. schtasks.exe
is natively found in `C:\Windows\system32` and `C:\Windows\syswow64`. The following
DLL(s) are loaded when schtasks.exe or TaskService is launched -`taskschd.dll`.
If found loaded by another process, it's possible a scheduled task is being registered
within that process context in memory. Upon triage, identify the task scheduled
source. Was it schtasks.exe or via TaskService? Review the job created and the Command
to be executed. Capture any artifacts on disk and review. Identify any parallel
processes within the same timeframe to identify source.'
data_source:
- Sysmon Event ID 7
search: '`sysmon` EventCode=7 parent_process_name IN ("WINWORD.EXE", "EXCEL.EXE",
"POWERPNT.EXE","onenote.exe","onenotem.exe","onenoteviewer.exe","onenoteim.exe",
"msaccess.exe") ImageLoaded = "*\\taskschd.dll" | stats min(_time) as firstTime
max(_time) as lastTime values(ImageLoaded) as AllImageLoaded count by Computer EventCode
Image parent_process_name ProcessId ProcessGuid | rename Computer as dest | `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)` | `office_document_creating_schedule_task_filter`'
how_to_implement: To successfully implement this search, you need to be ingesting
logs with the process name and ImageLoaded (Like sysmon EventCode 7) from your endpoints.
If you are using Sysmon, you must have at least version 6.0.4 of the Sysmon TA.
Also be sure to include those monitored dll to your own sysmon config.
known_false_positives: unknown
references:
- https://research.checkpoint.com/2021/irans-apt34-returns-with-an-updated-arsenal/
- https://redcanary.com/threat-detection-report/techniques/scheduled-task-job/
- https://www.trustwave.com/en-us/resources/blogs/spiderlabs-blog/trojanized-onenote-document-leads-to-formbook-malware/
tags:
analytic_story:
- Spearphishing Attachments
asset_type: Endpoint
confidence: 70
impact: 70
message: Office document creating a schedule task on $dest$
mitre_attack_id:
- T1566
- T1566.001
observable:
- name: dest
type: Endpoint
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
required_fields:
- ImageLoaded
- AllImageLoaded
- dest
- EventCode
- Image
- process_name
- ProcessId
- ProcessGuid
- _time
risk_score: 49
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1566.001/datasets/windows-sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: xmlwineventlog