TI Map URL Entity to AuditLogs

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Id	9991c277-e0a1-4079-8c40-fbfca2705615
Rulename	TI Map URL Entity to AuditLogs
Description	This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in AuditLogs.
Severity	Medium
Tactics	CommandAndControl
Techniques	T1071
Required data connectors	AzureActiveDirectory MicrosoftDefenderThreatIntelligence ThreatIntelligence ThreatIntelligenceTaxii
Kind	Scheduled
Query frequency	1h
Query period	14d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/URLEntity_AuditLogs.yaml
Version	1.2.9
Arm template	9991c277-e0a1-4079-8c40-fbfca2705615.json

KQL

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let AuditEvents = materialize(AuditLogs
  | where TimeGenerated >= ago(dt_lookBack)
  // Extract the URL that is contained within the JSON data
  | extend Url = extract("(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)", 1,tostring(TargetResources))
  | extend userPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)
  | extend TargetResourceDisplayName = tostring(TargetResources[0].displayName));
let AuditUrls = AuditEvents | distinct Url = tolower(Url) | summarize make_list(Url);
ThreatIntelIndicators
//extract key part of kv pair
     | extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
     | where IndicatorType == "url"
     | extend Url = toupper(ObservableValue)
     | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
| where TimeGenerated >= ago(ioc_lookBack)
| where tolower(Url) in (AuditUrls)
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
| where IsActive and (ValidUntil > now() or isempty(ValidUntil))
| extend Description = tostring(parse_json(Data).description)
| where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
// using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated
| join kind=innerunique (AuditEvents) on Url
| where TimeGenerated < ValidUntil
| summarize TimeGenerated = arg_max(TimeGenerated, *) by Id, Url
| extend Description = tostring(parse_json(Data).description)
| extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
| project TimeGenerated, Description, ActivityGroupNames, Id, Type, ValidUntil, Confidence,
OperationName, Identity, userPrincipalName, TargetResourceDisplayName, Url
| extend AccountName = tostring(split(userPrincipalName, "@")[0]), AccountUPNSuffix = tostring(split(userPrincipalName, "@")[1])
| extend HostName = tostring(split(TargetResourceDisplayName, ".")[0]), DomainIndex = toint(indexof(TargetResourceDisplayName, '.'))
| extend HostNameDomain = iff(DomainIndex != -1, substring(TargetResourceDisplayName, DomainIndex + 1), TargetResourceDisplayName)

YAML

name: TI Map URL Entity to AuditLogs
kind: Scheduled
description: |
    'This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in AuditLogs.'
entityMappings:
- entityType: Account
  fieldMappings:
  - columnName: userPrincipalName
    identifier: FullName
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
- entityType: Host
  fieldMappings:
  - columnName: TargetResourceDisplayName
    identifier: FullName
  - columnName: HostName
    identifier: HostName
  - columnName: HostNameDomain
    identifier: DnsDomain
- entityType: URL
  fieldMappings:
  - columnName: Url
    identifier: Url
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/URLEntity_AuditLogs.yaml
version: 1.2.9
triggerThreshold: 0
queryFrequency: 1h
triggerOperator: gt
relevantTechniques:
- T1071
tactics:
- CommandAndControl
requiredDataConnectors:
- connectorId: AzureActiveDirectory
  dataTypes:
  - AuditLogs
- connectorId: ThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: ThreatIntelligenceTaxii
  dataTypes:
  - ThreatIntelligenceIndicator
- connectorId: MicrosoftDefenderThreatIntelligence
  dataTypes:
  - ThreatIntelligenceIndicator
severity: Medium
queryPeriod: 14d
query: |
  let dt_lookBack = 1h;
  let ioc_lookBack = 14d;
  let AuditEvents = materialize(AuditLogs
    | where TimeGenerated >= ago(dt_lookBack)
    // Extract the URL that is contained within the JSON data
    | extend Url = extract("(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\(\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)", 1,tostring(TargetResources))
    | extend userPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)
    | extend TargetResourceDisplayName = tostring(TargetResources[0].displayName));
  let AuditUrls = AuditEvents | distinct Url = tolower(Url) | summarize make_list(Url);
  ThreatIntelIndicators
  //extract key part of kv pair
       | extend IndicatorType = replace(@"\[|\]|\""", "", tostring(split(ObservableKey, ":", 0)))
       | where IndicatorType == "url"
       | extend Url = toupper(ObservableValue)
       | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
  | where TimeGenerated >= ago(ioc_lookBack)
  | where tolower(Url) in (AuditUrls)
  | summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
  | where IsActive and (ValidUntil > now() or isempty(ValidUntil))
  | extend Description = tostring(parse_json(Data).description)
  | where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;"
  // using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated
  | join kind=innerunique (AuditEvents) on Url
  | where TimeGenerated < ValidUntil
  | summarize TimeGenerated = arg_max(TimeGenerated, *) by Id, Url
  | extend Description = tostring(parse_json(Data).description)
  | extend ActivityGroupNames = extract(@"ActivityGroup:(\S+)", 1, tostring(parse_json(Data).labels))
  | project TimeGenerated, Description, ActivityGroupNames, Id, Type, ValidUntil, Confidence,
  OperationName, Identity, userPrincipalName, TargetResourceDisplayName, Url
  | extend AccountName = tostring(split(userPrincipalName, "@")[0]), AccountUPNSuffix = tostring(split(userPrincipalName, "@")[1])
  | extend HostName = tostring(split(TargetResourceDisplayName, ".")[0]), DomainIndex = toint(indexof(TargetResourceDisplayName, '.'))
  | extend HostNameDomain = iff(DomainIndex != -1, substring(TargetResourceDisplayName, DomainIndex + 1), TargetResourceDisplayName)  
id: 9991c277-e0a1-4079-8c40-fbfca2705615

ARM

{
  "$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/9991c277-e0a1-4079-8c40-fbfca2705615')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/9991c277-e0a1-4079-8c40-fbfca2705615')]",
      "properties": {
        "alertRuleTemplateName": "9991c277-e0a1-4079-8c40-fbfca2705615",
        "customDetails": null,
        "description": "'This query identifies any URL indicators of compromise (IOCs) from threat intelligence (TI) by searching for matches in AuditLogs.'\n",
        "displayName": "TI Map URL Entity to AuditLogs",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "userPrincipalName",
                "identifier": "FullName"
              },
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "TargetResourceDisplayName",
                "identifier": "FullName"
              },
              {
                "columnName": "HostName",
                "identifier": "HostName"
              },
              {
                "columnName": "HostNameDomain",
                "identifier": "DnsDomain"
              }
            ]
          },
          {
            "entityType": "URL",
            "fieldMappings": [
              {
                "columnName": "Url",
                "identifier": "Url"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Threat Intelligence (NEW)/Analytic Rules/URLEntity_AuditLogs.yaml",
        "query": "let dt_lookBack = 1h;\nlet ioc_lookBack = 14d;\nlet AuditEvents = materialize(AuditLogs\n  | where TimeGenerated >= ago(dt_lookBack)\n  // Extract the URL that is contained within the JSON data\n  | extend Url = extract(\"(http[s]?://(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\\\\(\\\\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+)\", 1,tostring(TargetResources))\n  | extend userPrincipalName = tostring(parse_json(tostring(InitiatedBy.user)).userPrincipalName)\n  | extend TargetResourceDisplayName = tostring(TargetResources[0].displayName));\nlet AuditUrls = AuditEvents | distinct Url = tolower(Url) | summarize make_list(Url);\nThreatIntelIndicators\n//extract key part of kv pair\n     | extend IndicatorType = replace(@\"\\[|\\]|\\\"\"\", \"\", tostring(split(ObservableKey, \":\", 0)))\n     | where IndicatorType == \"url\"\n     | extend Url = toupper(ObservableValue)\n     | extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)\n| where TimeGenerated >= ago(ioc_lookBack)\n| where tolower(Url) in (AuditUrls)\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| where Description !contains_cs \"State: inactive;\" and Description !contains_cs \"State: falsepos;\"\n// using innerunique to keep perf fast and result set low, we only need one match to indicate potential malicious activity that needs to be investigated\n| join kind=innerunique (AuditEvents) on Url\n| where TimeGenerated < ValidUntil\n| summarize TimeGenerated = arg_max(TimeGenerated, *) by Id, Url\n| extend Description = tostring(parse_json(Data).description)\n| extend ActivityGroupNames = extract(@\"ActivityGroup:(\\S+)\", 1, tostring(parse_json(Data).labels))\n| project TimeGenerated, Description, ActivityGroupNames, Id, Type, ValidUntil, Confidence,\nOperationName, Identity, userPrincipalName, TargetResourceDisplayName, Url\n| extend AccountName = tostring(split(userPrincipalName, \"@\")[0]), AccountUPNSuffix = tostring(split(userPrincipalName, \"@\")[1])\n| extend HostName = tostring(split(TargetResourceDisplayName, \".\")[0]), DomainIndex = toint(indexof(TargetResourceDisplayName, '.'))\n| extend HostNameDomain = iff(DomainIndex != -1, substring(TargetResourceDisplayName, DomainIndex + 1), TargetResourceDisplayName)\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "CommandAndControl"
        ],
        "techniques": [
          "T1071"
        ],
        "templateVersion": "1.2.9",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}