GSA - TI Domain Entity

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let NetworkAccessTraff_ = NetworkAccessTraffic
| where TimeGenerated >= ago(dt_lookBack)
| where TrafficType == "internet"
| where isnotempty(DestinationFqdn)
| extend Domain = extract(@'([^.]+\.[^.]+)$', 1, DestinationFqdn)
| project-rename GSANetworkAccessTraffic_TimeGenerated = TimeGenerated;
let NetworkAccessTraffiDomains =
    NetworkAccessTraff_
    | distinct Domain;
ThreatIntelIndicators
  | extend IndicatorType = replace(@'\[|\]|"""', "", tostring(split(ObservableKey, ":", 0)))
  | where IndicatorType == "domain-name"
  | extend DomainName = tolower(ObservableValue)
  | where TimeGenerated >= ago(ioc_lookBack)
  | extend IndicatorId = tostring(split(Id, "--")[2])
  | where DomainName in (NetworkAccessTraffiDomains)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
  | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
  | extend Description = tostring(parse_json(Data).description)
  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
  | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
  | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type
  | join kind=innerunique (NetworkAccessTraff_) on $left.DomainName == $right.Domain
  | extend GSAThreatType = ThreatType
  | summarize GSANetworkAccessTraffic_TimeGenerated = arg_max(GSANetworkAccessTraffic_TimeGenerated, *) by Id, DestinationFqdn
  | project-reorder *,
    Tags,
    TrafficLightProtocolLevel,
    Type,
    DomainName,
    UserPrincipalName,
    UserId,
    DeviceId,
    InitiatingProcessName,
    GSAThreatType,
    DestinationUrl,
    DestinationPort,
    SourceIp,
    SourcePort,
    HttpUserAgent

name: GSA - TI Domain Entity
triggerOperator: gt
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let NetworkAccessTraff_ = NetworkAccessTraffic
  | where TimeGenerated >= ago(dt_lookBack)
  | where TrafficType == "internet"
  | where isnotempty(DestinationFqdn)
  | extend Domain = extract(@'([^.]+\.[^.]+)$', 1, DestinationFqdn)
  | project-rename GSANetworkAccessTraffic_TimeGenerated = TimeGenerated;
  let NetworkAccessTraffiDomains =
      NetworkAccessTraff_
      | distinct Domain;
  ThreatIntelIndicators
    | extend IndicatorType = replace(@'\[|\]|"""', "", tostring(split(ObservableKey, ":", 0)))
    | where IndicatorType == "domain-name"
    | extend DomainName = tolower(ObservableValue)
    | where TimeGenerated >= ago(ioc_lookBack)
    | extend IndicatorId = tostring(split(Id, "--")[2])
    | where DomainName in (NetworkAccessTraffiDomains)
    | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
    | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
    | extend Description = tostring(parse_json(Data).description)
    | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
    | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
    | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type
    | join kind=innerunique (NetworkAccessTraff_) on $left.DomainName == $right.Domain
    | extend GSAThreatType = ThreatType
    | summarize GSANetworkAccessTraffic_TimeGenerated = arg_max(GSANetworkAccessTraffic_TimeGenerated, *) by Id, DestinationFqdn
    | project-reorder *,
      Tags,
      TrafficLightProtocolLevel,
      Type,
      DomainName,
      UserPrincipalName,
      UserId,
      DeviceId,
      InitiatingProcessName,
      GSAThreatType,
      DestinationUrl,
      DestinationPort,
      SourceIp,
      SourcePort,
      HttpUserAgent
queryFrequency: 1h
description: |
  This query identifies Domain indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in GSA NetworkAccessTraffic.
id: 4ef07345-5d89-4f5b-9c64-a180d81a6176
triggerThreshold: 0
queryPeriod: 14d
kind: Scheduled
status: Available
severity: Medium
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - NetworkAccessTrafficLogs
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Global%20Secure%20Access/Analytic%20Rules/GSA%20-%20TI%20Domain%20Entity.yaml
relevantTechniques:
- T1071
tactics:
- CommandAndControl
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: UserPrincipalName
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIp
  entityType: IP
- fieldMappings:
  - identifier: Url
    columnName: DestinationFqdn
  entityType: URL
- fieldMappings:
  - identifier: CommandLine
    columnName: InitiatingProcessName
  entityType: Process

{
  "$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/4ef07345-5d89-4f5b-9c64-a180d81a6176')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4ef07345-5d89-4f5b-9c64-a180d81a6176')]",
      "properties": {
        "alertRuleTemplateName": "4ef07345-5d89-4f5b-9c64-a180d81a6176",
        "customDetails": null,
        "description": "This query identifies Domain indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in GSA NetworkAccessTraffic.\n",
        "displayName": "GSA - TI Domain Entity",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "UserPrincipalName",
                "identifier": "Name"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SourceIp",
                "identifier": "Address"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "DestinationFqdn",
                "identifier": "Url"
              }
            ]
          },
          {
            "entityType": "Process",
            "fieldMappings": [
              {
                "columnName": "InitiatingProcessName",
                "identifier": "CommandLine"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Global%20Secure%20Access/Analytic%20Rules/GSA%20-%20TI%20Domain%20Entity.yaml",
        "query": "let dt_lookBack = 1h;\nlet ioc_lookBack = 14d;\nlet NetworkAccessTraff_ = NetworkAccessTraffic\n| where TimeGenerated >= ago(dt_lookBack)\n| where TrafficType == \"internet\"\n| where isnotempty(DestinationFqdn)\n| extend Domain = extract(@'([^.]+\\.[^.]+)$', 1, DestinationFqdn)\n| project-rename GSANetworkAccessTraffic_TimeGenerated = TimeGenerated;\nlet NetworkAccessTraffiDomains =\n    NetworkAccessTraff_\n    | distinct Domain;\nThreatIntelIndicators\n  | extend IndicatorType = replace(@'\\[|\\]|\"\"\"', \"\", tostring(split(ObservableKey, \":\", 0)))\n  | where IndicatorType == \"domain-name\"\n  | extend DomainName = tolower(ObservableValue)\n  | where TimeGenerated >= ago(ioc_lookBack)\n  | extend IndicatorId = tostring(split(Id, \"--\")[2])\n  | where DomainName in (NetworkAccessTraffiDomains)\n  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue\n  | where IsActive and (ValidUntil > now() or isempty(ValidUntil))\n  | extend Description = tostring(parse_json(Data).description)\n  | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)\n  | where Description !contains_cs \"State: inactive;\" and Description !contains_cs \"State: falsepos;\"\n  | project-reorder *, IsActive, Tags, TrafficLightProtocolLevel, DomainName, Type\n  | join kind=innerunique (NetworkAccessTraff_) on $left.DomainName == $right.Domain\n  | extend GSAThreatType = ThreatType\n  | summarize GSANetworkAccessTraffic_TimeGenerated = arg_max(GSANetworkAccessTraffic_TimeGenerated, *) by Id, DestinationFqdn\n  | project-reorder *,\n    Tags,\n    TrafficLightProtocolLevel,\n    Type,\n    DomainName,\n    UserPrincipalName,\n    UserId,\n    DeviceId,\n    InitiatingProcessName,\n    GSAThreatType,\n    DestinationUrl,\n    DestinationPort,\n    SourceIp,\n    SourcePort,\n    HttpUserAgent\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "techniques": [
          "T1071"
        ],
        "templateVersion": "1.0.0",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}