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splunk-security_content/dev/endpoint/powershell_start_bitstransfer.yml
2023-01-23 09:38:17 +01:00

76 lines
2.7 KiB
YAML

name: PowerShell Start-BitsTransfer
id: 39e2605a-90d8-11eb-899e-acde48001122
version: 2
date: '2021-03-29'
author: Michael Haag, Splunk
status: production
type: TTP
description: Start-BitsTransfer is the PowerShell "version" of BitsAdmin.exe. Similar
functionality is present. This technique variation is not as commonly used by adversaries,
but has been abused in the past. Lesser known uses include the ability to set the
`-TransferType` to `Upload` for exfiltration of files. In an instance where `Upload`
is used, it is highly possible files will be archived. During triage, review parallel
processes and process lineage. Capture any files on disk and review. For the remote
domain or IP, what is the reputation?
data_source:
- Sysmon Event ID 1
search:
selection1:
OriginalFileName: pwsh.dll
selection2:
Image|endswith:
- pwsh.exe
- sqlps.exe
- sqltoolsps.exe
- powershell.exe
- powershell_ise.exe
selection3:
OriginalFileName: PowerShell.EXE
selection4:
OriginalFileName: powershell_ise.EXE
selection5:
CommandLine: '*start-bitstransfer*'
condition: (selection1 or selection2 or selection3 or selection4) and selection5
how_to_implement: To successfully implement this search you need to be ingesting information
on process that include the name of the process responsible for the changes from
your endpoints into the `Endpoint` datamodel in the `Processes` node. In addition,
confirm the latest CIM App 4.20 or higher is installed and the latest TA for the
endpoint product.
known_false_positives: Limited false positives. It is possible administrators will
utilize Start-BitsTransfer for administrative tasks, otherwise filter based parent
process or command-line arguments.
references:
- https://isc.sans.edu/diary/Investigating+Microsoft+BITS+Activity/23281
- https://docs.microsoft.com/en-us/windows/win32/bits/using-windows-powershell-to-create-bits-transfer-jobs
tags:
analytic_story:
- BITS Jobs
asset_type: Endpoint
confidence: 80
impact: 70
message: A suspicious process $process_name$ with commandline $process$ that are
related to bittransfer functionality in host $dest$
mitre_attack_id:
- T1197
observable:
- name: dest
type: Hostname
role:
- Victim
- name: user
type: User
role:
- Victim
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
risk_score: 56
security_domain: endpoint
tests:
- name: True Positive Test
attack_data:
- data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1197/atomic_red_team/windows-sysmon.log
source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
sourcetype: xmlwineventlog