Detection rules › Splunk

Windows Level RMM PowerShell Script Installer

Status
production
Severity
low
Group by
Guid, Name, Opcode, Path, ScriptBlockId, ScriptBlockText, computer_name, process_id, signature, signature_id, user_id, vendor_product
Author
Raven Tait, Splunk
Source
github.com/splunk/security_content

Detects the PowerShell installer for the Level tool. Level is a commercial remote management tool from Level.io. Remote management tools, when used for legitimate purposes, can help IT professionals and system administrators remotely access and manage computer systems. However, threat actors may exploit these tools for malicious purposes. It can be used to maintain persistence and execution on a host by a malicious actor.

MITRE ATT&CK coverage

TacticTechniques
Command & ControlT1219 Remote Access Tools

Event coverage

Rule body splunk

name: Windows Level RMM PowerShell Script Installer
id: 1abf472a-88c9-41bb-9002-3272037531b7
version: 2
creation_date: '2026-05-05'
modification_date: '2026-05-13'
author: Raven Tait, Splunk
status: production
type: Anomaly
description: |-
    Detects the PowerShell installer for the Level tool.
    Level is a commercial remote management tool from Level.io.
    Remote management tools, when used for legitimate purposes, can help IT professionals and system administrators remotely access and manage computer systems.
    However, threat actors may exploit these tools for malicious purposes.
    It can be used to maintain persistence and execution on a host by a malicious actor.
data_source:
    - Powershell Script Block Logging 4104
search: |-
    `powershell`
    EventID="4104"
    ScriptBlockText IN (
        "*$env:LEVEL_API_KEY *",
        "*https://downloads.level.io/install_windows.ps1*"
    )
    | fillnull
    | stats count min(_time) as firstTime
                  max(_time) as lastTime
      by Computer EventID ScriptBlockText signature signature_id user_id vendor_product Guid
         Opcode Name Path ProcessID ScriptBlockId
    
    | rename Computer as dest
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_level_rmm_powershell_script_installer_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: Legitimate IT and system administrators may use the Level PowerShell installer for remote management and maintenance. Filter alerts for authorized use within managed environments.
references:
    - https://www.cisa.gov/news-events/cybersecurity-advisories/aa23-320a
drilldown_searches:
    - earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
      name: View the detection results for - "$user$" and "$dest$"
      search: '%original_detection_search% | search  user = "$user$" dest = "$dest$"'
    - name: View risk events for the last 7 days for - "$user$" and "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$", "$dest$") | 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: 7d
      latest_offset: "0"
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 20
          message: Potential Level PowerShell installer activity observed on $dest$ via script block $ScriptBlockId$.
analytic_story:
    - Remote Monitoring and Management Software
asset_type: Endpoint
mitre_attack_id:
    - T1219
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1219/snapattack/snapattack.log
          source: XmlWinEventLog:Microsoft-Windows-PowerShell/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

Stages and Predicates

Stage 1: search

`powershell`
EventID="4104"
ScriptBlockText IN (
    "*$env:LEVEL_API_KEY *",
    "*https://downloads.level.io/install_windows.ps1*"
)

Stage 2: fillnull

| fillnull

Stage 3: stats

| stats count min(_time) as firstTime
              max(_time) as lastTime
  by Computer EventID ScriptBlockText signature signature_id user_id vendor_product Guid
     Opcode Name Path ProcessID ScriptBlockId

Stage 4: rename

| rename Computer as dest

Stage 5: search

| `security_content_ctime(firstTime)`

Stage 6: search

| `security_content_ctime(lastTime)`

Stage 7: search

| `windows_level_rmm_powershell_script_installer_filter`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventIDeq
  • "4104" corpus 268 (splunk 268)
ScriptBlockTextin
  • "*$env:LEVEL_API_KEY *"
  • "*https://downloads.level.io/install_windows.ps1*"