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
let OfficeActivity_ = materialize(OfficeActivity
  | where isnotempty(ClientIP)
  | where TimeGenerated >= ago(dt_lookBack)
  | 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]), '')
  | project-rename OfficeActivity_TimeGenerated = TimeGenerated);
let ActivityIPs = OfficeActivity_ | summarize IPs = make_list(IPAddress);
// Fetch threat intelligence indicators related to IP addresses
let IP_Indicators = materialize(ThreatIntelligenceIndicator
  | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
  | where TimeGenerated >= ago(ioc_lookBack)
  | extend TI_ipEntity = coalesce(NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress)
  | where TI_ipEntity in (ActivityIPs)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
  | where  Active == true and ExpirationDateTime > now()
  | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;");
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_)
  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])

relevantTechniques:
- T1071
name: TI map IP entity to OfficeActivity
requiredDataConnectors:
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: ThreatIntelligence
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: ThreatIntelligenceTaxii
- dataTypes:
  - ThreatIntelligenceIndicator
  connectorId: MicrosoftDefenderThreatIntelligence
- dataTypes:
  - OfficeActivity
  connectorId: Office365
entityMappings:
- fieldMappings:
  - identifier: FullName
    columnName: UserId
  - 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
triggerThreshold: 0
id: f15370f4-c6fa-42c5-9be4-1d308f40284e
tactics:
- CommandAndControl
version: 1.4.3
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence/Analytic Rules/IPEntity_OfficeActivity.yaml
queryPeriod: 14d
kind: Scheduled
queryFrequency: 1h
severity: Medium
description: |
    This query maps any IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in OfficeActivity.
query: |
  let dt_lookBack = 1h; // Look back 1 hour for OfficeActivity events
  let ioc_lookBack = 14d; // Look back 14 days for threat intelligence indicators
  let OfficeActivity_ = materialize(OfficeActivity
    | where isnotempty(ClientIP)
    | where TimeGenerated >= ago(dt_lookBack)
    | 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]), '')
    | project-rename OfficeActivity_TimeGenerated = TimeGenerated);
  let ActivityIPs = OfficeActivity_ | summarize IPs = make_list(IPAddress);
  // Fetch threat intelligence indicators related to IP addresses
  let IP_Indicators = materialize(ThreatIntelligenceIndicator
    | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)
    | where TimeGenerated >= ago(ioc_lookBack)
    | extend TI_ipEntity = coalesce(NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress)
    | where TI_ipEntity in (ActivityIPs)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId
    | where  Active == true and ExpirationDateTime > now()
    | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;");
  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_)
    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

{
  "$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/f15370f4-c6fa-42c5-9be4-1d308f40284e')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/f15370f4-c6fa-42c5-9be4-1d308f40284e')]",
      "properties": {
        "alertRuleTemplateName": "f15370f4-c6fa-42c5-9be4-1d308f40284e",
        "customDetails": null,
        "description": "This query maps any IP indicators of compromise (IOCs) from threat intelligence (TI), by searching for matches in OfficeActivity.\n",
        "displayName": "TI map IP entity to OfficeActivity",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserId",
                "identifier": "FullName"
              },
              {
                "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/Threat Intelligence/Analytic Rules/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\nlet OfficeActivity_ = materialize(OfficeActivity\n  | where isnotempty(ClientIP)\n  | where TimeGenerated >= ago(dt_lookBack)\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  | project-rename OfficeActivity_TimeGenerated = TimeGenerated);\nlet ActivityIPs = OfficeActivity_ | summarize IPs = make_list(IPAddress);\n// Fetch threat intelligence indicators related to IP addresses\nlet IP_Indicators = materialize(ThreatIntelligenceIndicator\n  | where isnotempty(NetworkIP) or isnotempty(EmailSourceIpAddress) or isnotempty(NetworkDestinationIP) or isnotempty(NetworkSourceIP)\n  | where TimeGenerated >= ago(ioc_lookBack)\n  | extend TI_ipEntity = coalesce(NetworkDestinationIP, NetworkSourceIP, EmailSourceIpAddress)\n  | where TI_ipEntity in (ActivityIPs)\n  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by IndicatorId\n  | where  Active == true and ExpirationDateTime > now()\n  | where Description !contains_cs \"State: inactive;\" and Description !contains_cs \"State: falsepos;\");\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 (OfficeActivity_)\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, 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",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "techniques": [
          "T1071"
        ],
        "templateVersion": "1.4.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}