Microsoft Sentinel Analytic Rules
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GreyNoise TI Map IP Entity to DnsEvents

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Idddf47b6f-870c-5712-a296-1383acb13c82
RulenameGreyNoise TI Map IP Entity to DnsEvents
DescriptionThis query maps any IP indicators of compromise (IOCs) from GreyNoise Threat Intelligence (TI), by searching for matches in DnsEvents.
SeverityMedium
TacticsCommandAndControl
TechniquesT1071
Required data connectorsASimDnsActivityLogs
DNS
GreyNoise2SentinelAPI
ThreatIntelligence
ThreatIntelligenceTaxii
KindScheduled
Query frequency1h
Query period14d
Trigger threshold0
Trigger operatorgt
Source Urihttps://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GreyNoiseThreatIntelligence/Analytic Rules/GreyNoise_IPEntity_DnsEvents.yaml
Version1.0.2
Arm templateddf47b6f-870c-5712-a296-1383acb13c82.json
Deploy To Azure
let dt_lookBack = 1h; // Look back 1 hour for DNS events
let ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators
// Fetch threat intelligence indicators related to IP addresses
let IP_Indicators = ThreatIntelligenceIndicator
  | where TimeGenerated >= ago(ioc_lookBack)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where Active == true and ExpirationDateTime > now()
  | where SourceSystem == 'GreyNoise'
  | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
  | extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
  | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
  | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)
  | where ipv4_is_private(TI_ipEntity) == false and  TI_ipEntity !startswith "fe80" and TI_ipEntity !startswith "::" and TI_ipEntity !startswith "127.";
// Perform a join between IP indicators and DNS events
IP_Indicators
  // Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation
  | join kind=innerunique (
      DnsEvents
      | where TimeGenerated >= ago(dt_lookBack)
      | where SubType =~ "LookupQuery" and isnotempty(IPAddresses)
      | mv-expand SingleIP = split(IPAddresses, ", ") to typeof(string)
      | extend DNS_TimeGenerated = TimeGenerated
  )
  on $left.TI_ipEntity == $right.SingleIP
  // Filter out DNS events that occurred after the expiration of the corresponding indicator
  | where DNS_TimeGenerated < ExpirationDateTime
  // Group the results by IndicatorId and SingleIP, and keep the DNS event with the latest timestamp
  | summarize DNS_TimeGenerated = arg_max(DNS_TimeGenerated, *) by IndicatorId, SingleIP
  // Select the desired output fields
  | project DNS_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, DomainName, ExpirationDateTime, ConfidenceScore,
    TI_ipEntity, Computer, EventId, SubType, ClientIP, Name, IPAddresses, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
  | extend timestamp = DNS_TimeGenerated, HostName = tostring(split(Computer, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(Computer, '.'), 1, -1), '.'))
id: ddf47b6f-870c-5712-a296-1383acb13c82
name: GreyNoise TI Map IP Entity to DnsEvents
triggerOperator: gt
query: |
  let dt_lookBack = 1h; // Look back 1 hour for DNS events
  let ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators
  // Fetch threat intelligence indicators related to IP addresses
  let IP_Indicators = ThreatIntelligenceIndicator
    | where TimeGenerated >= ago(ioc_lookBack)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
    | where Active == true and ExpirationDateTime > now()
    | where SourceSystem == 'GreyNoise'
    | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
    | extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)
    | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)
    | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)
    | where ipv4_is_private(TI_ipEntity) == false and  TI_ipEntity !startswith "fe80" and TI_ipEntity !startswith "::" and TI_ipEntity !startswith "127.";
  // Perform a join between IP indicators and DNS events
  IP_Indicators
    // Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation
    | join kind=innerunique (
        DnsEvents
        | where TimeGenerated >= ago(dt_lookBack)
        | where SubType =~ "LookupQuery" and isnotempty(IPAddresses)
        | mv-expand SingleIP = split(IPAddresses, ", ") to typeof(string)
        | extend DNS_TimeGenerated = TimeGenerated
    )
    on $left.TI_ipEntity == $right.SingleIP
    // Filter out DNS events that occurred after the expiration of the corresponding indicator
    | where DNS_TimeGenerated < ExpirationDateTime
    // Group the results by IndicatorId and SingleIP, and keep the DNS event with the latest timestamp
    | summarize DNS_TimeGenerated = arg_max(DNS_TimeGenerated, *) by IndicatorId, SingleIP
    // Select the desired output fields
    | project DNS_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, DomainName, ExpirationDateTime, ConfidenceScore,
      TI_ipEntity, Computer, EventId, SubType, ClientIP, Name, IPAddresses, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
    | extend timestamp = DNS_TimeGenerated, HostName = tostring(split(Computer, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(Computer, '.'), 1, -1), '.'))  
queryPeriod: 14d
triggerThreshold: 0
severity: Medium
queryFrequency: 1h
relevantTechniques:
- T1071
version: 1.0.2
kind: Scheduled
tactics:
- CommandAndControl
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GreyNoiseThreatIntelligence/Analytic Rules/GreyNoise_IPEntity_DnsEvents.yaml
entityMappings:
- fieldMappings:
  - identifier: HostName
    columnName: HostName
  - identifier: DnsDomain
    columnName: DnsDomain
  entityType: Host
- fieldMappings:
  - identifier: Address
    columnName: ClientIP
  entityType: IP
- fieldMappings:
  - identifier: Url
    columnName: Url
  entityType: URL
description: |
    This query maps any IP indicators of compromise (IOCs) from GreyNoise Threat Intelligence (TI), by searching for matches in DnsEvents.
requiredDataConnectors:
- connectorId: ThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: ThreatIntelligenceTaxii
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: DNS
  dataTypes:
  - DnsEvents
- connectorId: ASimDnsActivityLogs
  dataTypes:
  - DnsEvents
- connectorId: GreyNoise2SentinelAPI
  dataTypes:
  - ThreatIntelligenceIndicator
{
  "$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/ddf47b6f-870c-5712-a296-1383acb13c82')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/ddf47b6f-870c-5712-a296-1383acb13c82')]",
      "properties": {
        "alertRuleTemplateName": "ddf47b6f-870c-5712-a296-1383acb13c82",
        "customDetails": null,
        "description": "This query maps any IP indicators of compromise (IOCs) from GreyNoise Threat Intelligence (TI), by searching for matches in DnsEvents.\n",
        "displayName": "GreyNoise TI Map IP Entity to DnsEvents",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "DnsDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "ClientIP",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Url",
                "identifier": "Url"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GreyNoiseThreatIntelligence/Analytic Rules/GreyNoise_IPEntity_DnsEvents.yaml",
        "query": "let dt_lookBack = 1h; // Look back 1 hour for DNS events\nlet ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators\n// Fetch threat intelligence indicators related to IP addresses\nlet IP_Indicators = ThreatIntelligenceIndicator\n  | where TimeGenerated >= ago(ioc_lookBack)\n  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId\n  | where Active == true and ExpirationDateTime > now()\n  | where SourceSystem == 'GreyNoise'\n  | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)\n  | extend TI_ipEntity = iff(isnotempty(NetworkIP), NetworkIP, NetworkDestinationIP)\n  | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(NetworkSourceIP), NetworkSourceIP, TI_ipEntity)\n  | extend TI_ipEntity = iff(isempty(TI_ipEntity) and isnotempty(EmailSourceIpAddress), EmailSourceIpAddress, TI_ipEntity)\n  | where ipv4_is_private(TI_ipEntity) == false and  TI_ipEntity !startswith \"fe80\" and TI_ipEntity !startswith \"::\" and TI_ipEntity !startswith \"127.\";\n// Perform a join between IP indicators and DNS events\nIP_Indicators\n  // Use innerunique to keep performance fast and result set low, as we only need one match to indicate potential malicious activity that needs investigation\n  | join kind=innerunique (\n      DnsEvents\n      | where TimeGenerated >= ago(dt_lookBack)\n      | where SubType =~ \"LookupQuery\" and isnotempty(IPAddresses)\n      | mv-expand SingleIP = split(IPAddresses, \", \") to typeof(string)\n      | extend DNS_TimeGenerated = TimeGenerated\n  )\n  on $left.TI_ipEntity == $right.SingleIP\n  // Filter out DNS events that occurred after the expiration of the corresponding indicator\n  | where DNS_TimeGenerated < ExpirationDateTime\n  // Group the results by IndicatorId and SingleIP, and keep the DNS event with the latest timestamp\n  | summarize DNS_TimeGenerated = arg_max(DNS_TimeGenerated, *) by IndicatorId, SingleIP\n  // Select the desired output fields\n  | project DNS_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, DomainName, ExpirationDateTime, ConfidenceScore,\n    TI_ipEntity, Computer, EventId, SubType, ClientIP, Name, IPAddresses, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type\n  | extend timestamp = DNS_TimeGenerated, HostName = tostring(split(Computer, '.', 0)[0]), DnsDomain = tostring(strcat_array(array_slice(split(Computer, '.'), 1, -1), '.'))\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "techniques": [
          "T1071"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}