Detection: Windows Remote Management Execute Shell

Created: 2023-04-12 Last Updated: 2026-10-29 ID: 28b80028-851d-4b8d-88a5-375ba115418a Author: Drew Church, Michael Haag, Teoderick Contreras, Splunk Type: Anomaly Product: Splunk Enterprise Security

Description

This analytic detects selected processes spawned directly by Windows Remote Management Host processes winrshost.exe and wsmprovhost.exe. The selected children include shells, scripting hosts, and administrative, discovery, and file-transfer utilities. This target-side process relationship can indicate remote execution, but it can also result from authorized WinRM administration. Investigate the account, target host, available command line, and surrounding remote-logon activity to determine context.

Search

 1
 2| tstats `security_content_summariesonly`
 3  count min(_time) as firstTime
 4        max(_time) as lastTime
 5
 6FROM datamodel=Endpoint.Processes WHERE
 7
 8Processes.parent_process_name IN (
 9    "winrshost.exe",
10    "wsmprovhost.exe"
11)
12`windows_shells`
13NOT (
14        Processes.process_name="powershell.exe"
15        Processes.process="*-Version 5.1 -s -NoLogo -NoProfile"
16    )
17NOT (
18        Processes.process_name="cmd.exe"
19        (
20            (
21                Processes.process="*powershell -NoLogo -NonInteractive -NoProfile*"
22                Processes.process IN (
23                    "*Get-CimInstance MSFT_NetAdapter -Namespace *",
24                    "*Get-Command exsetup *",
25                    "*Get-Disk 
26| ForEach-Object*",
27                    "*HKLM:\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall*",
28                    "*HKLM:\\SYSTEM\\CurrentControlSet\\Control\\Class\\*",
29                    "*HKLM:\\SYSTEM\\CurrentControlSet\\Services\\*",
30                    "*New-Object Management.Automation.Host.Size*"
31                )
32            )
33            OR
34            Processes.process="* /c net start Veeam*"
35        )
36    )
37
38BY Processes.action Processes.dest Processes.original_file_name
39   Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
40   Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
41   Processes.process Processes.process_exec Processes.process_guid
42   Processes.process_hash Processes.process_id Processes.process_integrity_level
43   Processes.process_name Processes.process_path Processes.user
44   Processes.user_id Processes.vendor_product
45
46
47| `drop_dm_object_name(Processes)`
48
49| `security_content_ctime(firstTime)`
50
51| `security_content_ctime(lastTime)`
52
53| `windows_remote_management_execute_shell_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 1	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'`
Windows Event Log Security 4688	Windows	`'XmlWinEventLog'`	`'XmlWinEventLog:Security'`

Macros Used

Name	Value
windows_shells	`(Processes.process_name IN ("bash.exe", "cmd.exe", "powershell.exe", "powershell_ise.exe", "pwsh.exe", "sh.exe", "WindowsTerminal.exe", "wt.exe") OR Processes.original_file_name IN ("Cmd.Exe", "PowerShell.EXE", "pwsh.dll", "PowerShell_ISE.EXE"))`
windows_remote_management_execute_shell_filter	`search *`

windows_remote_management_execute_shell_filter is an empty macro by default. It allows the user to filter out any results (false positives) without editing the SPL.

Annotations

- MITRE ATT&CK

+ Kill Chain Phases

+ NIST

+ CIS

- Threat Actors

ID	Technique	Tactic
T1021.006	Windows Remote Management	Lateral Movement
T1059	Command and Scripting Interpreter	Execution

Exploitation

Installation

DE.AE

CIS 10

CVE

CVE-2021-31166

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Setting	Value
Disabled	true
Cron Schedule	`0 * * * *`
Earliest Time	`-70m@m`
Latest Time	`-10m@m`
Schedule Window	`auto`
Creates Finding (Notable)	No
Creates Intermediate Finding (Risk Event)	Yes

Anomaly detections generate Intermediate Findings (Risk Events). They do not generate a Finding (Notable) directly.

Implementation

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

Authorized administrators and management software may launch these processes through WinRM. Shell and discovery activity may be routine; evaluate expected accounts, hosts, and workflows before tuning.

Associated Analytic Story

Intermediate Findings

Message	Entity Field	Entity Type	Risk Score
Windows Remote Management process [$parent_process_name$] spawned [$process_name$] with CommandLine [$process$] on [$dest$].	dest	system	20

Threat Objects

Field	Type
process	process
process_name	process_name

References

Detection Testing

Test Type	Status	Dataset	Source	Sourcetype
Validation	✅ Passing	N/A	N/A	N/A
Unit	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`
Integration	✅ Passing	Dataset	`XmlWinEventLog:Microsoft-Windows-Sysmon/Operational`	`XmlWinEventLog`

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub |

Version: 9