Cisco WSA - Internet access from public IP

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Id	4250b050-e1c6-4926-af04-9484bbd7e94f
Rulename	Cisco WSA - Internet access from public IP
Description	Detects internet access from public IP.
Severity	Medium
Tactics	InitialAccess
Techniques	T1189
Required data connectors	CiscoWSA SyslogAma
Kind	Scheduled
Query frequency	1h
Query period	1h
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoWSA/Analytic Rules/CiscoWSAPublicIPSource.yaml
Version	1.0.1
Arm template	4250b050-e1c6-4926-af04-9484bbd7e94f.json

KQL

let ip_except = dynamic(['127.0.0.2']);    //Add exceptions to this list
CiscoWSAEvent
| where ipv4_is_private(SrcIpAddr) == false
| extend IPCustomEntity = SrcIpAddr

YAML

relevantTechniques:
- T1189
name: Cisco WSA - Internet access from public IP
requiredDataConnectors:
- dataTypes:
  - CiscoWSAEvent
  connectorId: CiscoWSA
- datatypes:
  - Syslog
  connectorId: SyslogAma
entityMappings:
- fieldMappings:
  - identifier: Address
    columnName: IPCustomEntity
  entityType: IP
triggerThreshold: 0
id: 4250b050-e1c6-4926-af04-9484bbd7e94f
tactics:
- InitialAccess
version: 1.0.1
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoWSA/Analytic Rules/CiscoWSAPublicIPSource.yaml
queryPeriod: 1h
kind: Scheduled
queryFrequency: 1h
severity: Medium
status: Available
description: |
    'Detects internet access from public IP.'
query: |
  let ip_except = dynamic(['127.0.0.2']);    //Add exceptions to this list
  CiscoWSAEvent
  | where ipv4_is_private(SrcIpAddr) == false
  | extend IPCustomEntity = SrcIpAddr  
triggerOperator: gt

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/4250b050-e1c6-4926-af04-9484bbd7e94f')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/4250b050-e1c6-4926-af04-9484bbd7e94f')]",
      "properties": {
        "alertRuleTemplateName": "4250b050-e1c6-4926-af04-9484bbd7e94f",
        "customDetails": null,
        "description": "'Detects internet access from public IP.'\n",
        "displayName": "Cisco WSA - Internet access from public IP",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "IPCustomEntity",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/CiscoWSA/Analytic Rules/CiscoWSAPublicIPSource.yaml",
        "query": "let ip_except = dynamic(['127.0.0.2']);    //Add exceptions to this list\nCiscoWSAEvent\n| where ipv4_is_private(SrcIpAddr) == false\n| extend IPCustomEntity = SrcIpAddr\n",
        "queryFrequency": "PT1H",
        "queryPeriod": "PT1H",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "InitialAccess"
        ],
        "techniques": [
          "T1189"
        ],
        "templateVersion": "1.0.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}