ForescoutHostProperties_CL | where HostProperties_DnsniffEvent_s matches regex "DNS Query Type:.A;DNS Query/Response:.Query" | extend ipaddress = iif(isnotempty(HostProperties_Ipv4Addr_s), HostProperties_Ipv4Addr_s, (iif(isnotempty(HostProperties_Ipv6Addr_s), HostProperties_Ipv6Addr_s, HostProperties_IpAddr_s))) | summarize NumEvents_d =count() by ipaddress, HostProperties_DnsniffEvent_s, HostProperties_EmIpAddr_s | where NumEvents_d > 2 | where isnotempty(ipaddress) and isnotempty(HostProperties_EmIpAddr_s) | sort by NumEvents_d asc | project NumEvents_d, ipaddress, HostProperties_EmIpAddr_s
queryFrequency: 5m
description: This rule creates an incident when more than certain number of Dnsniff events are generated from a host
customDetails:
NumEvents: NumEvents_d
Ip: ipaddress
EmIp: HostProperties_EmIpAddr_s
severity: Medium
version: 1.0.1
relevantTechniques: []
name: Forescout-DNS_Sniff_Event_Monitor
triggerThreshold: 0
kind: Scheduled
query: ForescoutHostProperties_CL | where HostProperties_DnsniffEvent_s matches regex "DNS Query Type:.A;DNS Query/Response:.Query" | extend ipaddress = iif(isnotempty(HostProperties_Ipv4Addr_s), HostProperties_Ipv4Addr_s, (iif(isnotempty(HostProperties_Ipv6Addr_s), HostProperties_Ipv6Addr_s, HostProperties_IpAddr_s))) | summarize NumEvents_d =count() by ipaddress, HostProperties_DnsniffEvent_s, HostProperties_EmIpAddr_s | where NumEvents_d > 2 | where isnotempty(ipaddress) and isnotempty(HostProperties_EmIpAddr_s) | sort by NumEvents_d asc | project NumEvents_d, ipaddress, HostProperties_EmIpAddr_s
alertDetailsOverride:
alertDisplayNameFormat: Dnsniff-Address-Check
alertDescriptionFormat: Dnsniff-Address-Check alert
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/ForescoutHostPropertyMonitor/Analytic Rules/ForeScout-DNSSniffEventMonitor.yaml
requiredDataConnectors: []
tactics: []
id: d272e277-f285-4dbc-ae2d-7f65ba64a79e
queryPeriod: 5m
entityMappings:
- fieldMappings:
- columnName: ipaddress
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/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 | where HostProperties_DnsniffEvent_s matches regex \"DNS Query Type:.A;DNS Query/Response:.Query\" | extend ipaddress = iif(isnotempty(HostProperties_Ipv4Addr_s), HostProperties_Ipv4Addr_s, (iif(isnotempty(HostProperties_Ipv6Addr_s), HostProperties_Ipv6Addr_s, HostProperties_IpAddr_s))) | summarize NumEvents_d =count() by ipaddress, HostProperties_DnsniffEvent_s, HostProperties_EmIpAddr_s | where NumEvents_d > 2 | where isnotempty(ipaddress) and isnotempty(HostProperties_EmIpAddr_s) | sort by NumEvents_d asc | project NumEvents_d, ipaddress, HostProperties_EmIpAddr_s",
"queryFrequency": "PT5M",
"queryPeriod": "PT5M",
"severity": "Medium",
"subTechniques": [],
"suppressionDuration": "PT1H",
"suppressionEnabled": false,
"tactics": [],
"techniques": [],
"templateVersion": "1.0.1",
"triggerOperator": "GreaterThan",
"triggerThreshold": 0
},
"type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
}
]
}