Query Tor Onion Address - DNS Client — Sigma Rule

Rule metadata and linked tags

Author: Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2022-02-20 / 2025-09-12.

{
  "product": "windows",
  "service": "dns-client",
  "definition": "Requirements: Microsoft-Windows-DNS Client Events/Operational Event Log must be enabled/collected in order to receive the events."
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 908c924be5f93aabe6e53dd2442b26b589de56a3ae97b66487d1a8fb4522058e

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Query Tor Onion Address - DNS Client
id: 8384bd26-bde6-4da9-8e5d-4174a7a47ca2
related:
    - id: b55ca2a3-7cff-4dda-8bdd-c7bfa63bf544
      type: similar
    - id: a8322756-015c-42e7-afb1-436e85ed3ff5
      type: similar
status: test
description: Detects DNS resolution of an .onion address related to Tor routing networks
references:
    - https://www.logpoint.com/en/blog/detecting-tor-use-with-logpoint/
    - https://github.com/Azure/Azure-Sentinel/blob/f99542b94afe0ad2f19a82cc08262e7ac8e1428e/Detections/ASimDNS/imDNS_TorProxies.yaml
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-02-20
modified: 2025-09-12
tags:
    - attack.command-and-control
    - attack.t1090.003
logsource:
    product: windows
    service: dns-client
    definition: 'Requirements: Microsoft-Windows-DNS Client Events/Operational Event Log must be enabled/collected in order to receive the events.'
detection:
    selection:
        EventID: 3008
        QueryName|endswith:
            - '.hiddenservice.net'
            - '.onion.ca'
            - '.onion.cab'
            - '.onion.casa'
            - '.onion.city'
            - '.onion.direct'
            - '.onion.dog'
            - '.onion.glass'
            - '.onion.gq'
            - '.onion.guide'
            - '.onion.in.net'
            - '.onion.ink'
            - '.onion.it'
            - '.onion.link'
            - '.onion.lt'
            - '.onion.lu'
            - '.onion.ly'
            - '.onion.mn'
            - '.onion.network'
            - '.onion.nu'
            - '.onion.pet'
            - '.onion.plus'
            - '.onion.pt'
            - '.onion.pw'
            - '.onion.rip'
            - '.onion.sh'
            - '.onion.si'
            - '.onion.to'
            - '.onion.top'
            - '.onion.ws'
            - '.onion'
            - '.s1.tor-gateways.de'
            - '.s2.tor-gateways.de'
            - '.s3.tor-gateways.de'
            - '.s4.tor-gateways.de'
            - '.s5.tor-gateways.de'
            - '.t2w.pw'
            - '.tor2web.ae.org'
            - '.tor2web.blutmagie.de'
            - '.tor2web.com'
            - '.tor2web.fi'
            - '.tor2web.io'
            - '.tor2web.org'
            - '.tor2web.xyz'
            - '.torlink.co'
    condition: selection
falsepositives:
    - Unlikely
level: high

Original YAML and metadata in JSON

False positives

• Unlikely

Source references

• https://www.logpoint.com/en/blog/detecting-tor-use-with-logpoint/
• https://github.com/Azure/Azure-Sentinel/blob/f99542b94afe0ad2f19a82cc08262e7ac8e1428e/Detections/ASimDNS/imDNS_TorProxies.yaml