splunk_escuTTP

Powershell Windows Defender Exclusion Commands

The following analytic detects the use of PowerShell commands to add or set Windows Defender exclusions. It leverages EventCode 4104 to identify suspicious `Add-MpPreference` or `Set-MpPreference` commands with exclusion parameters. This activity is significant because adversaries often use it to bypass Windows Defender, allowing malicious code to execute without detection. If confirmed malicious, this behavior could enable attackers to evade antivirus defenses, maintain persistence, and execute further malicious activities undetected.

MITRE ATT&CK

T1562.001

Detection Query

`powershell` EventCode=4104 (ScriptBlockText = "*Add-MpPreference *" OR ScriptBlockText = "*Set-MpPreference *") AND ScriptBlockText = "*-exclusion*"
  | 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)`
  | `powershell_windows_defender_exclusion_commands_filter`

Author

Teoderick Contreras, Splunk

Created

2026-03-10

Data Sources

Powershell Script Block Logging 4104

References

Tags

CISA AA22-320AAgentTeslaRemcosWindows Defense Evasion TacticsData DestructionWhisperGateWarzone RATNetSupport RMM Tool AbuseBlankGrabber Stealer

Raw Content

name: Powershell Windows Defender Exclusion Commands
id: 907ac95c-4dd9-11ec-ba2c-acde48001122
version: 12
date: '2026-03-10'
author: Teoderick Contreras, Splunk
status: production
type: TTP
description: The following analytic detects the use of PowerShell commands to add or set Windows Defender exclusions. It leverages EventCode 4104 to identify suspicious `Add-MpPreference` or `Set-MpPreference` commands with exclusion parameters. This activity is significant because adversaries often use it to bypass Windows Defender, allowing malicious code to execute without detection. If confirmed malicious, this behavior could enable attackers to evade antivirus defenses, maintain persistence, and execute further malicious activities undetected.
data_source:
    - Powershell Script Block Logging 4104
search: |-
    `powershell` EventCode=4104 (ScriptBlockText = "*Add-MpPreference *" OR ScriptBlockText = "*Set-MpPreference *") AND ScriptBlockText = "*-exclusion*"
      | 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)`
      | `powershell_windows_defender_exclusion_commands_filter`
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 `Registry` node. Also make sure that this registry was included in your config files ex. sysmon config to be monitored.
known_false_positives: admin or user may choose to use this windows features.
references:
    - https://tccontre.blogspot.com/2020/01/remcos-rat-evading-windows-defender-av.html
    - https://app.any.run/tasks/cf1245de-06a7-4366-8209-8e3006f2bfe5/
    - https://www.microsoft.com/security/blog/2022/01/15/destructive-malware-targeting-ukrainian-organizations/
drilldown_searches:
    - name: View the detection results for - "$user_id$" and "$dest$"
      search: '%original_detection_search% | search  user_id = "$user_id$" dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user_id$" and "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user_id$", "$dest$") 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: Exclusion command $ScriptBlockText$ executed on $dest$
    risk_objects:
        - field: user_id
          type: user
          score: 50
        - field: dest
          type: system
          score: 50
    threat_objects: []
tags:
    analytic_story:
        - CISA AA22-320A
        - AgentTesla
        - Remcos
        - Windows Defense Evasion Tactics
        - Data Destruction
        - WhisperGate
        - Warzone RAT
        - NetSupport RMM Tool Abuse
        - BlankGrabber Stealer
    asset_type: Endpoint
    mitre_attack_id:
        - T1562.001
    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/T1562.001/powershell_windows_defender_exclusion_commands/windows-xml.log
          source: XmlWinEventLog:Microsoft-Windows-PowerShell/Operational
          sourcetype: XmlWinEventLog