Ollama Abnormal Network Connectivity

name: Ollama Abnormal Network Connectivity
id: 19ec30ad-faa2-496a-a6a9-f2e5f778fbdb
version: 6
creation_date: '2025-10-13'
modification_date: '2026-10-09'
author: Rod Soto, Nasreddine Bencherchali, Splunk
status: production
type: Anomaly
description: |-
    Detects repeated Ollama warning-level network errors, such as DNS lookup failures, TCP connection issues, or host resolution problems. These events can indicate a connectivity issue and warrant investigation, but do not by themselves establish unauthorized access or reconnaissance.
data_source:
    - Ollama Server
search: |-
    `ollama_server`
    level=WARN
    msg IN (
        "*connection*",
        "*dial tcp*",
        "*failed*",
        "*lookup*",
        "*network*",
        "*no such host*",
        "*refused*",
        "*timeout*",
        "*unreachable*"
    )

    | bin _time span=5m
    | stats count as incidents
            values(msg) as warning_messages
            latest(_time) as last_incident
      by _time dest

    | where incidents > 3

    | eval last_incident=strftime(last_incident, "%Y-%m-%d %H:%M:%S")

    | eval severity="medium"

    | eval attack_type="Abnormal Network Connectivity"

    | table last_incident dest incidents warning_messages severity attack_type

    | `ollama_abnormal_network_connectivity_filter`
how_to_implement: |-
    Ingest Ollama logs via Splunk TA-ollama add-on by configuring file monitoring inputs pointed to your Ollama server log directories (sourcetype: ollama:server), or enable HTTP Event Collector (HEC) for real-time API telemetry and prompt analytics (sourcetypes: ollama:api, ollama:prompts). CIM compatibility using the Web datamodel for standardized security detections.
known_false_positives: |-
    Legitimate remote access from authorized users or applications connecting from non-localhost addresses, temporary network infrastructure issues causing DNS resolution failures, firewall or network configuration changes resulting in connection timeouts, cloud-hosted Ollama instances receiving valid external API requests, or intermittent connectivity problems during network maintenance may trigger this detection during normal operations.
references:
    - https://github.com/rosplk/ta-ollama
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"
intermediate_findings:
    entities:
        - field: dest
          type: system
          score: 20
          message: Abnormal network activity on [$dest$] with [$incidents$] matching warnings [$warning_messages$]. Investigate DNS and network reachability.
analytic_story:
    - Suspicious Ollama Activities
asset_type: Web Application
mitre_attack_id: []
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: application
security_domain: endpoint
tests:
    - name: True Positive Test
      attack_data:
        - data: https://media.githubusercontent.com/media/splunk/attack_data/master/datasets/ollama/app.log
          sourcetype: ollama:server
          source: app.log
      test_type: unit