Zero Networks Segment - Rare JIT Rule Creation

let starttime = 14d;
let endtime = 1d;
ZNSegmentAudit
| where TimeGenerated >= ago(endtime)
| where AuditTypeId == 20
| extend PerformedByName = tostring(InitiatedBy.Name),
    DestinationEntityName = tostring(AffectedEntity.Name)
| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), ConnectionCount = count()
by PerformedByName, DestinationEntityName
  // use left anti to exclude anything from the previous 14 days that is not rare
| join kind=leftanti (
ZNSegmentAudit
| where TimeGenerated between (ago(starttime) .. ago(endtime))
| where AuditTypeId == 20
| extend DestinationEntityName = tostring(AffectedEntity.Name)
| summarize by DestinationEntityName
) on DestinationEntityName
| summarize StartTime = min(StartTime), EndTime = max(EndTime), ConnectionCount = sum(ConnectionCount)
by PerformedByName, DestinationEntityName
| extend TimeGenerated = StartTime

name: Zero Networks Segment - Rare JIT Rule Creation
triggerOperator: gt
query: |
  let starttime = 14d;
  let endtime = 1d;
  ZNSegmentAudit
  | where TimeGenerated >= ago(endtime)
  | where AuditTypeId == 20
  | extend PerformedByName = tostring(InitiatedBy.Name),
      DestinationEntityName = tostring(AffectedEntity.Name)
  | summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), ConnectionCount = count()
  by PerformedByName, DestinationEntityName
    // use left anti to exclude anything from the previous 14 days that is not rare
  | join kind=leftanti (
  ZNSegmentAudit
  | where TimeGenerated between (ago(starttime) .. ago(endtime))
  | where AuditTypeId == 20
  | extend DestinationEntityName = tostring(AffectedEntity.Name)
  | summarize by DestinationEntityName
  ) on DestinationEntityName
  | summarize StartTime = min(StartTime), EndTime = max(EndTime), ConnectionCount = sum(ConnectionCount)
  by PerformedByName, DestinationEntityName
  | extend TimeGenerated = StartTime
queryFrequency: 1d
description: |
  'Identifies when a JIT Rule connection is new or rare by a given account today based on comparison with the previous 14 days.
  JIT Rule creations are indicated by the Activity Type Id 20'
id: 58688058-68b2-4b39-8009-ac6dc4d81ea1
triggerThreshold: 0
queryPeriod: 14d
version: 1.0.3
kind: Scheduled
status: Available
severity: Medium
requiredDataConnectors:
- connectorId: ZeroNetworksSegmentAuditFunction
  dataTypes:
  - ZNSegmentAudit_CL
- connectorId: ZeroNetworksSegmentAuditNativePoller
  dataTypes:
  - ZNSegmentAuditNativePoller_CL
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/ZeroNetworks/Analytic%20Rules/ZNSegmentRareJITRuleCreation.yaml
relevantTechniques:
- T1021
tactics:
- LateralMovement
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: PerformedByName
  entityType: Account
- fieldMappings:
  - identifier: HostName
    columnName: DestinationEntityName
  entityType: Host

{
  "$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/58688058-68b2-4b39-8009-ac6dc4d81ea1')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/58688058-68b2-4b39-8009-ac6dc4d81ea1')]",
      "properties": {
        "alertRuleTemplateName": "58688058-68b2-4b39-8009-ac6dc4d81ea1",
        "customDetails": null,
        "description": "'Identifies when a JIT Rule connection is new or rare by a given account today based on comparison with the previous 14 days.\nJIT Rule creations are indicated by the Activity Type Id 20'\n",
        "displayName": "Zero Networks Segment - Rare JIT Rule Creation",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "PerformedByName",
                "identifier": "Name"
              }
            ]
          },
          {
            "entityType": "Host",
            "fieldMappings": [
              {
                "columnName": "DestinationEntityName",
                "identifier": "HostName"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/ZeroNetworks/Analytic%20Rules/ZNSegmentRareJITRuleCreation.yaml",
        "query": "let starttime = 14d;\nlet endtime = 1d;\nZNSegmentAudit\n| where TimeGenerated >= ago(endtime)\n| where AuditTypeId == 20\n| extend PerformedByName = tostring(InitiatedBy.Name),\n    DestinationEntityName = tostring(AffectedEntity.Name)\n| summarize StartTime = min(TimeGenerated), EndTime = max(TimeGenerated), ConnectionCount = count()\nby PerformedByName, DestinationEntityName\n  // use left anti to exclude anything from the previous 14 days that is not rare\n| join kind=leftanti (\nZNSegmentAudit\n| where TimeGenerated between (ago(starttime) .. ago(endtime))\n| where AuditTypeId == 20\n| extend DestinationEntityName = tostring(AffectedEntity.Name)\n| summarize by DestinationEntityName\n) on DestinationEntityName\n| summarize StartTime = min(StartTime), EndTime = max(EndTime), ConnectionCount = sum(ConnectionCount)\nby PerformedByName, DestinationEntityName\n| extend TimeGenerated = StartTime\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P14D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "LateralMovement"
        ],
        "techniques": [
          "T1021"
        ],
        "templateVersion": "1.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}