Windows Set Custom DNS ServerLevelPlugin Via Dnscmd

SPLUNK detection rule by Raven Tait, Splunk · Apache-2.0

The following analytic detects command-line usage of dnscmd.exe to configure the Microsoft DNS ServerLevelPluginDll setting. This setting allows the DNS service to load an arbitrary DLL, which can be abused by attackers with DNS administrative privileges to execute code in the context of the DNS service. If confirmed malicious, this activity could enable persistence, privilege escalation, or domain controller compromise through malicious DLL loading.

name: Windows Set Custom DNS ServerLevelPlugin Via Dnscmd
id: 9add7765-4af5-45aa-a078-3b32de303e3e
version: 2
creation_date: '2026-05-05'
modification_date: '2026-05-13'
author: Raven Tait, Splunk
status: production
type: Anomaly
description: |-
    The following analytic detects command-line usage of dnscmd.exe to configure the Microsoft DNS ServerLevelPluginDll setting.
    This setting allows the DNS service to load an arbitrary DLL, which can be abused by attackers with DNS administrative privileges to execute code in the context of the DNS service.
    If confirmed malicious, this activity could enable persistence, privilege escalation, or domain controller compromise through malicious DLL loading.
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

    Processes.process_name="dnscmd.exe"
    Processes.process="*/config *"
    Processes.process="*/serverlevelplugindll *"

    by Processes.process Processes.vendor_product Processes.user_id Processes.process_hash
       Processes.parent_process_name Processes.parent_process_exec Processes.action
       Processes.dest Processes.process_current_directory Processes.process_path
       Processes.process_integrity_level Processes.original_file_name Processes.parent_process
       Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id
       Processes.process_guid Processes.process_id Processes.user Processes.process_name

    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_set_custom_dns_serverlevelplugin_via_dnscmd_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 administrative activities may involve dnscmd.exe usage or registry changes for DLL management in DNS servers. Filter alerts to exclude authorized administrative actions.
references:
    - https://medium.com/@esnesenon/feature-not-bug-dnsadmin-to-dc-compromise-in-one-line-a0f779b8dc83
    - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/dnscmd
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: 50
          message: Potential DNS ServerLevelPlugin DLL configuration observed on $dest$ via $process$.
threat_objects:
    - field: parent_process_name
      type: parent_process_name
analytic_story:
    - Windows Persistence Techniques
asset_type: Endpoint
mitre_attack_id:
    - T1574
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/T1574/snapattack/snapattack.log
          source: XmlWinEventLog:Security
          sourcetype: XmlWinEventLog
      test_type: unit

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