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DNS events related to ToR proxies ASIM DNS Schema

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Id3fe3c520-04f1-44b8-8398-782ed21435f8
RulenameDNS events related to ToR proxies (ASIM DNS Schema)
DescriptionIdentifies IP addresses performing DNS lookups associated with common ToR proxies.

This analytic rule uses ASIM and supports any built-in or custom source that supports the ASIM DNS schema
SeverityLow
TacticsExfiltration
TechniquesT1048
Required data connectorsAzureFirewall
CiscoUmbrellaDataConnector
Corelight
DNS
GCPDNSDataConnector
InfobloxNIOS
NXLogDnsLogs
Zscaler
KindScheduled
Query frequency1d
Query period1d
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDNS_TorProxies.yaml
Version1.3.4
Arm template3fe3c520-04f1-44b8-8398-782ed21435f8.json
Deploy To Azure
let torProxies=dynamic(["tor2web.org", "tor2web.com", "torlink.co", "onion.to", "onion.ink", "onion.cab", "onion.nu", "onion.link", 
"onion.it", "onion.city", "onion.direct", "onion.top", "onion.casa", "onion.plus", "onion.rip", "onion.dog", "tor2web.fi", 
"tor2web.blutmagie.de", "onion.sh", "onion.lu", "onion.pet", "t2w.pw", "tor2web.ae.org", "tor2web.io", "tor2web.xyz", "onion.lt", 
"s1.tor-gateways.de", "s2.tor-gateways.de", "s3.tor-gateways.de", "s4.tor-gateways.de", "s5.tor-gateways.de", "hiddenservice.net"]);
_Im_Dns(domain_has_any=torProxies)
| extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
| project-away DomainIndex
description: |
  'Identifies IP addresses performing DNS lookups associated with common ToR proxies.
  This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM DNS schema'  
queryPeriod: 1d
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDNS_TorProxies.yaml
id: 3fe3c520-04f1-44b8-8398-782ed21435f8
kind: Scheduled
requiredDataConnectors:
- connectorId: DNS
  dataTypes:
  - DnsEvents
- connectorId: AzureFirewall
  dataTypes:
  - AzureDiagnostics
- connectorId: Zscaler
  dataTypes:
  - CommonSecurityLog
- connectorId: InfobloxNIOS
  dataTypes:
  - Syslog
- connectorId: GCPDNSDataConnector
  dataTypes:
  - GCP_DNS_CL
- connectorId: NXLogDnsLogs
  dataTypes:
  - NXLog_DNS_Server_CL
- connectorId: CiscoUmbrellaDataConnector
  dataTypes:
  - Cisco_Umbrella_dns_CL
- connectorId: Corelight
  dataTypes:
  - Corelight_CL
metadata:
  support:
    tier: Community
  source:
    kind: Community
  categories:
    domains:
    - Security - Network
  author:
    name: Yaron Fruchtmann
tactics:
- Exfiltration
severity: Low
triggerOperator: gt
tags:
- ParentAlert: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/DnsEvents/DNS_TorProxies.yaml
  version: 1.0.0
- Schema: ASIMDns
  SchemaVersion: 0.1.1
version: 1.3.4
query: |
  let torProxies=dynamic(["tor2web.org", "tor2web.com", "torlink.co", "onion.to", "onion.ink", "onion.cab", "onion.nu", "onion.link", 
  "onion.it", "onion.city", "onion.direct", "onion.top", "onion.casa", "onion.plus", "onion.rip", "onion.dog", "tor2web.fi", 
  "tor2web.blutmagie.de", "onion.sh", "onion.lu", "onion.pet", "t2w.pw", "tor2web.ae.org", "tor2web.io", "tor2web.xyz", "onion.lt", 
  "s1.tor-gateways.de", "s2.tor-gateways.de", "s3.tor-gateways.de", "s4.tor-gateways.de", "s5.tor-gateways.de", "hiddenservice.net"]);
  _Im_Dns(domain_has_any=torProxies)
  | extend HostName = tostring(split(Dvc, ".")[0]), DomainIndex = toint(indexof(Dvc, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)
  | project-away DomainIndex  
name: DNS events related to ToR proxies  (ASIM DNS Schema)
queryFrequency: 1d
relevantTechniques:
- T1048
entityMappings:
- fieldMappings:
  - columnName: Dvc
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: DnsDomain
  entityType: Host
- fieldMappings:
  - columnName: SrcIpAddr
    identifier: Address
  entityType: IP
{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2024-01-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/3fe3c520-04f1-44b8-8398-782ed21435f8')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/3fe3c520-04f1-44b8-8398-782ed21435f8')]",
      "properties": {
        "alertRuleTemplateName": "3fe3c520-04f1-44b8-8398-782ed21435f8",
        "customDetails": null,
        "description": "'Identifies IP addresses performing DNS lookups associated with common ToR proxies.\nThis analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM DNS schema'\n",
        "displayName": "DNS events related to ToR proxies  (ASIM DNS Schema)",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "Dvc",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SrcIpAddr",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDNS_TorProxies.yaml",
        "query": "let torProxies=dynamic([\"tor2web.org\", \"tor2web.com\", \"torlink.co\", \"onion.to\", \"onion.ink\", \"onion.cab\", \"onion.nu\", \"onion.link\", \n\"onion.it\", \"onion.city\", \"onion.direct\", \"onion.top\", \"onion.casa\", \"onion.plus\", \"onion.rip\", \"onion.dog\", \"tor2web.fi\", \n\"tor2web.blutmagie.de\", \"onion.sh\", \"onion.lu\", \"onion.pet\", \"t2w.pw\", \"tor2web.ae.org\", \"tor2web.io\", \"tor2web.xyz\", \"onion.lt\", \n\"s1.tor-gateways.de\", \"s2.tor-gateways.de\", \"s3.tor-gateways.de\", \"s4.tor-gateways.de\", \"s5.tor-gateways.de\", \"hiddenservice.net\"]);\n_Im_Dns(domain_has_any=torProxies)\n| extend HostName = tostring(split(Dvc, \".\")[0]), DomainIndex = toint(indexof(Dvc, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(Dvc, DomainIndex + 1), Dvc)\n| project-away DomainIndex\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Low",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Exfiltration"
        ],
        "tags": [
          {
            "ParentAlert": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/DnsEvents/DNS_TorProxies.yaml",
            "version": "1.0.0"
          },
          {
            "Schema": "ASIMDns",
            "SchemaVersion": "0.1.1"
          }
        ],
        "techniques": [
          "T1048"
        ],
        "templateVersion": "1.3.4",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}