Excessive NXDOMAIN DNS Queries ASIM DNS Schema

let threshold = 200;
_Im_Dns(responsecodename='NXDOMAIN')
| where isnotempty(DnsResponseCodeName)
//| where DnsResponseCodeName =~ "NXDOMAIN"
| summarize count() by SrcIpAddr, bin(TimeGenerated,15m)
| where count_ > threshold
| join kind=inner (_Im_Dns(responsecodename='NXDOMAIN')
    ) on SrcIpAddr

triggerOperator: gt
queryFrequency: 1h
description: |
  'This creates an incident in the event a client generates excessive amounts of DNS queries for non-existent domains. 
  This analytic rule uses [ASIM](https://aka.ms/AboutASIM) and supports any built-in or custom source that supports the ASIM DNS schema'  
version: 1.3.4
kind: Scheduled
triggerThreshold: 0
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
queryPeriod: 1h
name: Excessive NXDOMAIN DNS Queries (ASIM DNS Schema)
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDns_ExcessiveNXDOMAINDNSQueries.yaml
id: c3b11fb2-9201-4844-b7b9-6b7bf6d9b851
tags:
- ParentAlert: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/InfobloxNIOS/ExcessiveNXDOMAINDNSQueries.yaml
  version: 1.0.0
- Schema: ASIMDns
  SchemaVersion: 0.1.1
tactics:
- CommandAndControl
metadata:
  source:
    kind: Community
  author:
    name: Yaron
  categories:
    domains:
    - Security - Network
  support:
    tier: Community
relevantTechniques:
- T1568
- T1008
severity: Medium
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: SrcIpAddr
  entityType: IP
query: |
  let threshold = 200;
  _Im_Dns(responsecodename='NXDOMAIN')
  | where isnotempty(DnsResponseCodeName)
  //| where DnsResponseCodeName =~ "NXDOMAIN"
  | summarize count() by SrcIpAddr, bin(TimeGenerated,15m)
  | where count_ > threshold
  | join kind=inner (_Im_Dns(responsecodename='NXDOMAIN')
      ) on SrcIpAddr  

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/c3b11fb2-9201-4844-b7b9-6b7bf6d9b851')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/c3b11fb2-9201-4844-b7b9-6b7bf6d9b851')]",
      "properties": {
        "alertRuleTemplateName": "c3b11fb2-9201-4844-b7b9-6b7bf6d9b851",
        "customDetails": null,
        "description": "'This creates an incident in the event a client generates excessive amounts of DNS queries for non-existent domains. \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": "Excessive NXDOMAIN DNS Queries (ASIM DNS Schema)",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SrcIpAddr",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDns_ExcessiveNXDOMAINDNSQueries.yaml",
        "query": "let threshold = 200;\n_Im_Dns(responsecodename='NXDOMAIN')\n| where isnotempty(DnsResponseCodeName)\n//| where DnsResponseCodeName =~ \"NXDOMAIN\"\n| summarize count() by SrcIpAddr, bin(TimeGenerated,15m)\n| where count_ > threshold\n| join kind=inner (_Im_Dns(responsecodename='NXDOMAIN')\n    ) on SrcIpAddr\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "tags": [
          {
            "ParentAlert": "https://github.com/Azure/Azure-Sentinel/blob/master/Detections/InfobloxNIOS/ExcessiveNXDOMAINDNSQueries.yaml",
            "version": "1.0.0"
          },
          {
            "Schema": "ASIMDns",
            "SchemaVersion": "0.1.1"
          }
        ],
        "techniques": [
          "T1008",
          "T1568"
        ],
        "templateVersion": "1.3.4",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}