Forescout-DNS_Sniff_Event_Monitor

ForescoutHostProperties_CL | extend  d = parse_json(HostProperties) | where d.DnsniffEvent matches regex "DNS Query Type:.A;DNS Query/Response:.Query" | extend ipaddress = iif(isnotempty(Ipv4Addr), Ipv4Addr, (iif(isnotempty(Ipv6Addr), Ipv6Addr, ""))) | where isnotempty(ipaddress) and isnotempty(EmIpAddr) | summarize NumEvents_d =count() by ipaddress, EmIpAddr | where NumEvents_d > 2 | sort by NumEvents_d asc | project NumEvents_d, ipaddress, EmIpAddr

queryPeriod: 5m
queryFrequency: 5m
name: Forescout-DNS_Sniff_Event_Monitor
id: d272e277-f285-4dbc-ae2d-7f65ba64a79e
entityMappings:
- entityType: IP
  fieldMappings:
  - columnName: ipaddress
    identifier: Address
customDetails:
  EmIp: HostProperties_EmIpAddr_s
  Ip: ipaddress
  NumEvents: NumEvents_d
query: ForescoutHostProperties_CL | extend  d = parse_json(HostProperties) | where d.DnsniffEvent matches regex "DNS Query Type:.A;DNS Query/Response:.Query" | extend ipaddress = iif(isnotempty(Ipv4Addr), Ipv4Addr, (iif(isnotempty(Ipv6Addr), Ipv6Addr, ""))) | where isnotempty(ipaddress) and isnotempty(EmIpAddr) | summarize NumEvents_d =count() by ipaddress, EmIpAddr | where NumEvents_d > 2 | sort by NumEvents_d asc | project NumEvents_d, ipaddress, EmIpAddr
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/ForescoutHostPropertyMonitor/Analytic Rules/ForeScout-DNSSniffEventMonitor.yaml
requiredDataConnectors: []
relevantTechniques: []
alertDetailsOverride:
  alertDisplayNameFormat: Dnsniff-Address-Check
  alertDescriptionFormat: Dnsniff-Address-Check alert
description: This rule creates an incident when more than certain number of Dnsniff events are generated from a host
tactics: []
severity: Medium
triggerThreshold: 0
version: 1.0.2
kind: Scheduled
triggerOperator: gt

{
  "$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/d272e277-f285-4dbc-ae2d-7f65ba64a79e')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/d272e277-f285-4dbc-ae2d-7f65ba64a79e')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Dnsniff-Address-Check alert",
          "alertDisplayNameFormat": "Dnsniff-Address-Check"
        },
        "alertRuleTemplateName": "d272e277-f285-4dbc-ae2d-7f65ba64a79e",
        "customDetails": {
          "EmIp": "HostProperties_EmIpAddr_s",
          "Ip": "ipaddress",
          "NumEvents": "NumEvents_d"
        },
        "description": "This rule creates an incident when more than certain number of Dnsniff events are generated from a host",
        "displayName": "Forescout-DNS_Sniff_Event_Monitor",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "ipaddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/ForescoutHostPropertyMonitor/Analytic Rules/ForeScout-DNSSniffEventMonitor.yaml",
        "query": "ForescoutHostProperties_CL | extend  d = parse_json(HostProperties) | where d.DnsniffEvent matches regex \"DNS Query Type:.A;DNS Query/Response:.Query\" | extend ipaddress = iif(isnotempty(Ipv4Addr), Ipv4Addr, (iif(isnotempty(Ipv6Addr), Ipv6Addr, \"\"))) | where isnotempty(ipaddress) and isnotempty(EmIpAddr) | summarize NumEvents_d =count() by ipaddress, EmIpAddr | where NumEvents_d > 2 | sort by NumEvents_d asc | project NumEvents_d, ipaddress, EmIpAddr",
        "queryFrequency": "PT5M",
        "queryPeriod": "PT5M",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [],
        "techniques": [],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}