Detection rules › Splunk
Remote Process Instantiation via DCOM and PowerShell Script Block
The following analytic detects the execution of PowerShell commands that initiate a process on a remote endpoint via the DCOM protocol. It leverages PowerShell Script Block Logging (EventCode=4104) to identify the use of ShellExecute and ExecuteShellCommand. This activity is significant as it may indicate lateral movement or remote code execution attempts by adversaries. If confirmed malicious, this behavior could allow attackers to execute arbitrary code on remote systems, potentially leading to further compromise and persistence within the network.
Known false positives
- Administrators may leverage DCOM to start a process on remote systems, but this activity is usually limited to a small set of hosts or users.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Lateral Movement |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| PowerShell | Event ID 4104: Creating Scriptblock text (MessageNumber of MessageTotal). |
Rule body
name: Remote Process Instantiation via DCOM and PowerShell Script Block
id: fa1c3040-4680-11ec-a618-3e22fbd008af
version: 13
creation_date: '2021-11-15'
modification_date: '2026-05-13'
author: Mauricio Velazco, Splunk
status: production
type: TTP
description: The following analytic detects the execution of PowerShell commands that initiate a process on a remote endpoint via the DCOM protocol. It leverages PowerShell Script Block Logging (EventCode=4104) to identify the use of ShellExecute and ExecuteShellCommand. This activity is significant as it may indicate lateral movement or remote code execution attempts by adversaries. If confirmed malicious, this behavior could allow attackers to execute arbitrary code on remote systems, potentially leading to further compromise and persistence within the network.
data_source:
- Powershell Script Block Logging 4104
search: |-
`powershell` EventCode=4104 (ScriptBlockText="*Document.Application.ShellExecute*" OR ScriptBlockText="*Document.ActiveView.ExecuteShellCommand*")
| fillnull
| stats count min(_time) as firstTime max(_time) as lastTime
BY dest signature signature_id
user_id vendor_product EventID
Guid Opcode Name
Path ProcessID ScriptBlockId
ScriptBlockText
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `remote_process_instantiation_via_dcom_and_powershell_script_block_filter`
how_to_implement: To successfully implement this analytic, you will need to enable PowerShell Script Block Logging on some or all endpoints. Additional setup instructions can be found https://help.splunk.com/en/security-offerings/splunk-user-behavior-analytics/get-data-in/5.4.1/add-other-data-to-splunk-uba/configure-powershell-logging-to-see-powershell-anomalies-in-splunk-uba.
known_false_positives: Administrators may leverage DCOM to start a process on remote systems, but this activity is usually limited to a small set of hosts or users.
references:
- https://attack.mitre.org/techniques/T1021/003/
- https://www.cybereason.com/blog/dcom-lateral-movement-techniques
finding:
title: A process was started on a remote endpoint from $dest$ by abusing WMI using PowerShell.exe
entity:
field: dest
type: system
score: 50
analytic_story:
- Active Directory Lateral Movement
asset_type: Endpoint
mitre_attack_id:
- T1021.003
product:
- Splunk Enterprise
- Splunk Enterprise Security
- Splunk Cloud
category: endpoint
security_domain: endpoint
Stages and Predicates
Stage 1: search
`powershell` EventCode=4104 (ScriptBlockText="*Document.Application.ShellExecute*" OR ScriptBlockText="*Document.ActiveView.ExecuteShellCommand*")
Stage 2: fillnull
| fillnull
Stage 3: stats
| stats count min(_time) as firstTime max(_time) as lastTime
BY dest signature signature_id
user_id vendor_product EventID
Guid Opcode Name
Path ProcessID ScriptBlockId
ScriptBlockText
Stage 4: search
| `security_content_ctime(firstTime)`
Stage 5: search
| `security_content_ctime(lastTime)`
Stage 6: search
| `remote_process_instantiation_via_dcom_and_powershell_script_block_filter`
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
EventCode | eq |
| field:"EventID" kind:eq value:"4104" |
ScriptBlockText | eq |
| field:"ScriptBlockText" kind:eq |