Windows DNS Query Request To TinyUrl

SPLUNK detection rule by Teoderick Contreras, Splunk · Apache-2.0

The following analytic detects a process located in a potentially suspicious location making DNS queries to known URL shortening services, specifically tinyurl. URL shorteners are frequently used by threat actors to obfuscate malicious destinations, including phishing pages, malware distribution sites, or command-and-control (C2) endpoints. While tinyurl.com is a legitimate service, its use in enterprise environments—particularly by non-browser processes or scripts—should be considered suspicious, especially if correlated with subsequent outbound connections, file downloads, process file path or credential prompts. Analysts should investigate the source process, execution context, and destination domain to determine intent and risk.

name: Windows DNS Query Request To TinyUrl
id: b1ea79da-719c-437c-acaf-5c93f838f425
version: 5
creation_date: '2021-11-18'
modification_date: '2026-05-13'
author: Teoderick Contreras, Splunk
status: production
type: Anomaly
description: |
    The following analytic detects a process located in a potentially suspicious location making DNS queries to known URL shortening services, specifically tinyurl.
    URL shorteners are frequently used by threat actors to obfuscate malicious destinations, including phishing pages, malware distribution sites, or command-and-control (C2) endpoints.
    While tinyurl.com is a legitimate service, its use in enterprise environments—particularly by non-browser processes or scripts—should be considered suspicious, especially if correlated with subsequent outbound connections, file downloads, process file path or credential prompts. Analysts should investigate the source process, execution context, and destination domain to determine intent and risk.
data_source:
    - Sysmon EventID 22
search: |
    `sysmon`
    EventCode=22
    QueryName = "tinyurl.com"
    Image IN (
      "*\\AppData\\*",
      "*\\Perflogs\\*",
      "*\\ProgramData\\*",
      "*\\Temp\\*",
      "*\\Users\\Public\\*",
      "*\\Windows\\Tasks\\*"
      )
    | stats count min(_time) as firstTime max(_time) as lastTime
      by answer answer_count dvc process_exec process_guid process_name query query_count
         reply_code_id signature signature_id src user_id vendor_product QueryName QueryResults QueryStatus
    | `security_content_ctime(firstTime)`
    | `security_content_ctime(lastTime)`
    | `windows_dns_query_request_to_tinyurl_filter`
how_to_implement: |
    This detection relies on sysmon logs with the Event ID 22, DNS Query.
    We suggest you run this detection at least once a day over the last 14 days.
known_false_positives: |
    Noise and false positive can be seen if the following instant
    messaging is allowed to use within corporate network. In this case, a filter is needed.
references:
    - https://x.com/Unit42_Intel/status/1919418143476199869
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: dvc
          type: system
          score: 20
          message: Suspicious process $process_name$ made a DNS query for $QueryName$ on $dvc$
threat_objects:
    - field: process_name
      type: process_name
analytic_story:
    - Malicious Inno Setup Loader
asset_type: Endpoint
mitre_attack_id:
    - T1105
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/T1105/tinyurl_dns_query/tinyurl.log
          source: XmlWinEventLog:Microsoft-Windows-Sysmon/Operational
          sourcetype: XmlWinEventLog
      test_type: unit

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

f4fa509e-5635-4b43-aaa5-c0f7135c6389

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

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Format & documentation suggestions

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