Windows Finger.exe Connecting to a Remote Host

name: Windows Finger.exe Connecting to a Remote Host
id: 86a5686a-7bc4-469c-9f88-2620279ede6e
version: 1
creation_date: '2026-09-16'
modification_date: '2026-09-16'
author: Onur Mustafa Erdogan, Splunk
status: production
type: TTP
description: |-
    The following analytic identifies the `finger.exe` utility being spawned with a command line containing an `@` character, indicating a remote host/server was specified.
    The Finger protocol utility is largely obsolete in modern environments and has been abused by adversaries as a living-off-the-land binary (LOLBIN) to retrieve encoded payloads or establish covert command-and-control communication with an attacker-controlled finger server.
    This behavior is uncommon in legitimate enterprise usage and warrants investigation.
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="finger.exe"
        OR
        Processes.original_file_name="finger.exe"
    )
    Processes.process="*@*"

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

    | `drop_dm_object_name(Processes)`
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_finger_exe_connecting_to_a_remote_host_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: No false positives have been identified at this time.
references:
    - https://packetwatch.com/resources/threat-profile/clickfix-abuses-finger-to-deliver-castleloader
    - https://lolbas-project.github.io/lolbas/Binaries/Finger/
drilldown_searches:
    - name: View the detection results for - "$dest$"
      search: '%original_detection_search% | search  dest = "$dest$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$dest$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$dest$") | 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'
finding:
    title: The [$process_path$] utility was used to connect to a remote host via the Command Line [$process$] from [$dest$]
    entity:
        field: dest
        type: system
        score: 50
threat_objects:
    - field: process
      type: process
analytic_story:
    - Command And Control
    - Compromised Windows Host
    - Fake CAPTCHA Campaigns
    - Windows Post-Exploitation
    - Living Off The Land
asset_type: Endpoint
mitre_attack_id:
    - T1071
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/T1071/finger_remote_host/finger_remote_host.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit