GreyNoise TI map IP entity to OfficeActivity

let dt_lookBack = 1h; // Look back 1 hour for OfficeActivity 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 OfficeActivity 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 (
      OfficeActivity
      | where TimeGenerated >= ago(dt_lookBack)
      | where isnotempty(ClientIP)
      | extend ClientIPValues = extract_all(@'\[?(::ffff:)?(?P<IPAddress>(\d+\.\d+\.\d+\.\d+)|[^\]%]+)(%\d+)?\]?([-:](?P<Port>\d+))?', dynamic(["IPAddress", "Port"]), ClientIP)[0]
      | extend IPAddress = iff(array_length(ClientIPValues) > 0, tostring(ClientIPValues[0]), '')
      | extend OfficeActivity_TimeGenerated = TimeGenerated
  )
  on $left.TI_ipEntity == $right.IPAddress
  // Filter out OfficeActivity events that occurred after the expiration of the corresponding indicator
  | where OfficeActivity_TimeGenerated < ExpirationDateTime
  // Group the results by IndicatorId and keep the OfficeActivity event with the latest timestamp
  | summarize OfficeActivity_TimeGenerated = arg_max(OfficeActivity_TimeGenerated, *) by IndicatorId
  // Select the desired output fields
  | project OfficeActivity_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
    TI_ipEntity, ClientIP, UserId, Operation, ResultStatus, RecordType, OfficeObjectId, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
  | extend timestamp = OfficeActivity_TimeGenerated, Name = tostring(split(UserId, '@', 0)[0]), UPNSuffix = tostring(split(UserId, '@', 1)[0])

OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GreyNoiseThreatIntelligence/Analytic Rules/GreyNoise_IPEntity_OfficeActivity.yaml
requiredDataConnectors:
- connectorId: ThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: ThreatIntelligenceTaxii
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: MicrosoftDefenderThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: Office365
  dataTypes:
  - OfficeActivity
- connectorId: GreyNoise2SentinelAPI
  dataTypes:
  - ThreatIntelligenceIndicator
query: |
  let dt_lookBack = 1h; // Look back 1 hour for OfficeActivity 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 OfficeActivity 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 (
        OfficeActivity
        | where TimeGenerated >= ago(dt_lookBack)
        | where isnotempty(ClientIP)
        | extend ClientIPValues = extract_all(@'\[?(::ffff:)?(?P<IPAddress>(\d+\.\d+\.\d+\.\d+)|[^\]%]+)(%\d+)?\]?([-:](?P<Port>\d+))?', dynamic(["IPAddress", "Port"]), ClientIP)[0]
        | extend IPAddress = iff(array_length(ClientIPValues) > 0, tostring(ClientIPValues[0]), '')
        | extend OfficeActivity_TimeGenerated = TimeGenerated
    )
    on $left.TI_ipEntity == $right.IPAddress
    // Filter out OfficeActivity events that occurred after the expiration of the corresponding indicator
    | where OfficeActivity_TimeGenerated < ExpirationDateTime
    // Group the results by IndicatorId and keep the OfficeActivity event with the latest timestamp
    | summarize OfficeActivity_TimeGenerated = arg_max(OfficeActivity_TimeGenerated, *) by IndicatorId
    // Select the desired output fields
    | project OfficeActivity_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,
      TI_ipEntity, ClientIP, UserId, Operation, ResultStatus, RecordType, OfficeObjectId, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type
    | extend timestamp = OfficeActivity_TimeGenerated, Name = tostring(split(UserId, '@', 0)[0]), UPNSuffix = tostring(split(UserId, '@', 1)[0])  
triggerOperator: gt
severity: Medium
description: |
    This query maps any GreyNoise IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in OfficeActivity.
tactics:
- Impact
triggerThreshold: 0
kind: Scheduled
queryFrequency: 1h
name: GreyNoise TI map IP entity to OfficeActivity
version: 1.0.0
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: Name
  - identifier: UPNSuffix
    columnName: UPNSuffix
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: TI_ipEntity
  entityType: IP
- fieldMappings:
  - identifier: Url
    columnName: Url
  entityType: URL
id: c51628fe-999c-5150-9fd7-660fc4f58ed2
queryPeriod: 14d

{
  "$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/c51628fe-999c-5150-9fd7-660fc4f58ed2')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/c51628fe-999c-5150-9fd7-660fc4f58ed2')]",
      "properties": {
        "alertRuleTemplateName": "c51628fe-999c-5150-9fd7-660fc4f58ed2",
        "customDetails": null,
        "description": "This query maps any GreyNoise IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in OfficeActivity.\n",
        "displayName": "GreyNoise TI map IP entity to OfficeActivity",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "Name",
                "identifier": "Name"
              },
              {
                "columnName": "UPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "TI_ipEntity",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Url",
                "identifier": "Url"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/GreyNoiseThreatIntelligence/Analytic Rules/GreyNoise_IPEntity_OfficeActivity.yaml",
        "query": "let dt_lookBack = 1h; // Look back 1 hour for OfficeActivity 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 OfficeActivity 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      OfficeActivity\n      | where TimeGenerated >= ago(dt_lookBack)\n      | where isnotempty(ClientIP)\n      | extend ClientIPValues = extract_all(@'\\[?(::ffff:)?(?P<IPAddress>(\\d+\\.\\d+\\.\\d+\\.\\d+)|[^\\]%]+)(%\\d+)?\\]?([-:](?P<Port>\\d+))?', dynamic([\"IPAddress\", \"Port\"]), ClientIP)[0]\n      | extend IPAddress = iff(array_length(ClientIPValues) > 0, tostring(ClientIPValues[0]), '')\n      | extend OfficeActivity_TimeGenerated = TimeGenerated\n  )\n  on $left.TI_ipEntity == $right.IPAddress\n  // Filter out OfficeActivity events that occurred after the expiration of the corresponding indicator\n  | where OfficeActivity_TimeGenerated < ExpirationDateTime\n  // Group the results by IndicatorId and keep the OfficeActivity event with the latest timestamp\n  | summarize OfficeActivity_TimeGenerated = arg_max(OfficeActivity_TimeGenerated, *) by IndicatorId\n  // Select the desired output fields\n  | project OfficeActivity_TimeGenerated, Description, ActivityGroupNames, IndicatorId, ThreatType, Url, ExpirationDateTime, ConfidenceScore,\n    TI_ipEntity, ClientIP, UserId, Operation, ResultStatus, RecordType, OfficeObjectId, NetworkIP, NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress, Type\n  | extend timestamp = OfficeActivity_TimeGenerated, Name = tostring(split(UserId, '@', 0)[0]), UPNSuffix = tostring(split(UserId, '@', 1)[0])\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Impact"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}