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Idc3b11fb2-9201-4844-b7b9-6b7bf6d9b851
RulenameExcessive NXDOMAIN DNS Queries (ASIM DNS Schema)
DescriptionThis creates an incident in the event a client generates excessive amounts of DNS queries for non-existent domains.

This analytic rule uses ASIM and supports any built-in or custom source that supports the ASIM DNS schema
SeverityMedium
TacticsCommandAndControl
TechniquesT1568
T1008
Required data connectorsAzureFirewall
CiscoUmbrellaDataConnector
Corelight
DNS
GCPDNSDataConnector
InfobloxNIOS
NXLogDnsLogs
Zscaler
KindScheduled
Query frequency1h
Query period1h
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDns_ExcessiveNXDOMAINDNSQueries.yaml
Version1.3.4
Arm templatec3b11fb2-9201-4844-b7b9-6b7bf6d9b851.json
Deploy To Azure
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
name: Excessive NXDOMAIN DNS Queries (ASIM DNS Schema)
triggerOperator: gt
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
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'
id: c3b11fb2-9201-4844-b7b9-6b7bf6d9b851
triggerThreshold: 0
queryPeriod: 1h
version: 1.3.4
kind: Scheduled
relevantTechniques:
- T1568
- T1008
tags:
- ParentAlert: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/InfobloxNIOS/ExcessiveNXDOMAINDNSQueries.yaml
  version: 1.0.0
- SchemaVersion: 0.1.1
  Schema: ASIMDns
severity: Medium
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:
  categories:
    domains:
    - Security - Network
  support:
    tier: Community
  author:
    name: Yaron
  source:
    kind: Community
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Detections/ASimDNS/imDns_ExcessiveNXDOMAINDNSQueries.yaml
tactics:
- CommandAndControl
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: SrcIpAddr
  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/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",
        "subTechniques": [],
        "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"
    }
  ]
}