mirror of
https://github.com/splunk/security_content
synced 2026-06-08 17:32:49 +00:00
Eric
87 lines
4.5 KiB
YAML
87 lines
4.5 KiB
YAML
name: PowerShell Start-BitsTransfer
|
|
id: 39e2605a-90d8-11eb-899e-acde48001122
|
|
version: 8
|
|
date: '2025-05-02'
|
|
author: Michael Haag, Splunk
|
|
status: production
|
|
type: TTP
|
|
description: The following analytic detects the execution of the PowerShell command
|
|
`Start-BitsTransfer`, which can be used for file transfers, including potential
|
|
data exfiltration. It leverages data from Endpoint Detection and Response (EDR)
|
|
agents, focusing on process creation events and command-line arguments. This activity
|
|
is significant because `Start-BitsTransfer` can be abused by adversaries to upload
|
|
sensitive files to remote locations, posing a risk of data loss. If confirmed malicious,
|
|
this could lead to unauthorized data exfiltration, compromising sensitive information
|
|
and potentially leading to further exploitation of the network.
|
|
data_source:
|
|
- Sysmon EventID 1
|
|
- Windows Event Log Security 4688
|
|
- CrowdStrike ProcessRollup2
|
|
search: '| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time)
|
|
as lastTime from datamodel=Endpoint.Processes where `process_powershell` Processes.process=*start-bitstransfer*
|
|
by Processes.action Processes.dest Processes.original_file_name Processes.parent_process
|
|
Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id
|
|
Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec
|
|
Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level
|
|
Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
|
|
| `drop_dm_object_name(Processes)` | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`
|
|
| `powershell_start_bitstransfer_filter`'
|
|
how_to_implement: The detection is based on data that originates from Endpoint Detection
|
|
and Response (EDR) agents. These agents are designed to provide security-related
|
|
telemetry from the endpoints where the agent is installed. To implement this search,
|
|
you must ingest logs that contain the process GUID, process name, and parent process.
|
|
Additionally, you must ingest complete command-line executions. These logs must
|
|
be processed using the appropriate Splunk Technology Add-ons that are specific to
|
|
the EDR product. The logs must also be mapped to the `Processes` node of the `Endpoint`
|
|
data model. Use the Splunk Common Information Model (CIM) to normalize the field
|
|
names and speed up the data modeling process.
|
|
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
|
|
drilldown_searches:
|
|
- name: View the detection results for - "$dest$" and "$user$"
|
|
search: '%original_detection_search% | search dest = "$dest$" user = "$user$"'
|
|
earliest_offset: $info_min_time$
|
|
latest_offset: $info_max_time$
|
|
- name: View risk events for the last 7 days for - "$dest$" and "$user$"
|
|
search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$",
|
|
"$user$") starthoursago=168 | 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: $info_min_time$
|
|
latest_offset: $info_max_time$
|
|
rba:
|
|
message: A suspicious process $process_name$ with commandline $process$ that are
|
|
related to bittransfer functionality in host $dest$
|
|
risk_objects:
|
|
- field: dest
|
|
type: system
|
|
score: 56
|
|
- field: user
|
|
type: user
|
|
score: 56
|
|
threat_objects: []
|
|
tags:
|
|
analytic_story:
|
|
- BITS Jobs
|
|
- Gozi Malware
|
|
asset_type: Endpoint
|
|
mitre_attack_id:
|
|
- T1197
|
|
product:
|
|
- Splunk Enterprise
|
|
- Splunk Enterprise Security
|
|
- Splunk Cloud
|
|
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
|