Linux Suspicious Docker Build Command Execution

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

The following analytic detects docker build being executed on Dockerfiles within the /tmp directory. This is not a typical location for this activity and can indicate an actor adding a container for malicious future actions.

name: Linux Suspicious Docker Build Command Execution
id: dc4a58d2-fde3-4bdd-a36b-7368b2523589
version: 1
creation_date: '2026-07-08'
modification_date: '2026-07-08'
author: Raven Tait, Splunk
status: production
type: Anomaly
description: |-
    The following analytic detects docker build being executed on Dockerfiles within the /tmp directory.
    This is not a typical location for this activity and can indicate an actor adding a container for malicious future actions.
data_source:
    - Sysmon for Linux EventID 1
search: |-
    | tstats `security_content_summariesonly`
      count min(_time) as firstTime max(_time) as lastTime

    from datamodel=Endpoint.Processes where

    Processes.process="*docker*"
    Processes.process="*build*"
    (
        (
            Processes.process="*-f *"
            Processes.process="* /tmp*"
        )
        OR
        Processes.process_current_directory="/tmp*"
    )

    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)`
    | `linux_suspicious_docker_build_command_execution_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: |-
    Developers or administrators may occasionally use the /tmp directory for testing Docker builds in non-production environments. Filter based on known users or systems where this activity has been approved.
references:
    - https://github.com/Aegrah/PANIX
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: Suspicious Docker Build Command [$process$] observed on [$dest$] executed by [$user$].
threat_objects:
    - field: process_name
      type: process_name
    - field: process
      type: process
analytic_story:
    - Linux Post-Exploitation
asset_type: Endpoint
mitre_attack_id:
    - T1610
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: endpoint
security_domain: endpoint
tests:
    - name: True Positive Test
      test_type: unit
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/attack_techniques/T1610/linux_suspicious_docker_build/snapattack_linux.log
          source: Syslog:Linux-Sysmon/Operational
          sourcetype: sysmon:linux

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949964c2-e4d5-4474-87eb-8a5b6a7c2003

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