AWSCloudTrail - Changes to Amazon VPC settings

let EventNameList = dynamic(["CreateNetworkAclEntry","CreateRoute","CreateRouteTable","CreateInternetGateway","CreateNatGateway"]);
AWSCloudTrail
| where EventName in~ (EventNameList)
| where EventSource != "apigateway.amazonaws.com"
| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
| extend UserName = tostring(split(UserIdentityArn, '/')[-1])
| extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
| extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
  AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by EventName, EventTypeName, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, UserIdentityPrincipalid, UserAgent,
UserIdentityUserName, SessionMfaAuthenticated, SourceIpAddress, AWSRegion, EventSource, AdditionalEventData, ResponseElements

requiredDataConnectors:
- dataTypes:
  - AWSCloudTrail
  connectorId: AWS
- dataTypes:
  - AWSCloudTrail
  connectorId: AWSS3
version: 1.0.8
severity: Low
triggerOperator: gt
query: |
  let EventNameList = dynamic(["CreateNetworkAclEntry","CreateRoute","CreateRouteTable","CreateInternetGateway","CreateNatGateway"]);
  AWSCloudTrail
  | where EventName in~ (EventNameList)
  | where EventSource != "apigateway.amazonaws.com"
  | extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)
  | extend UserName = tostring(split(UserIdentityArn, '/')[-1])
  | extend AccountName = case( UserIdentityPrincipalid == "Anonymous", "Anonymous", isempty(UserIdentityUserName), UserName, UserIdentityUserName)
  | extend AccountName = iif(AccountName contains "@", tostring(split(AccountName, '@', 0)[0]), AccountName),
    AccountUPNSuffix = iif(AccountName contains "@", tostring(split(AccountName, '@', 1)[0]), "")
  | summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by EventName, EventTypeName, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, UserIdentityPrincipalid, UserAgent,
  UserIdentityUserName, SessionMfaAuthenticated, SourceIpAddress, AWSRegion, EventSource, AdditionalEventData, ResponseElements
tactics:
- PrivilegeEscalation
- DefenseEvasion
status: Available
customDetails:
  EventName: EventName
  RecipientAccountId: RecipientAccountId
  EventSource: EventSource
  AWSRegion: AWSRegion
name: AWSCloudTrail - Changes to Amazon VPC settings
description: |
  Identifies changes to Amazon VPC(Virtual Private Cloud) settings that can alter network exposure, routing, or access controls.
  This rule identifies changes to Amazon VPC (Virtual Private Cloud) settings such as new ACL entries, routes, routetable or Gateways. 
  AWS VPC API Docs: https://docs.aws.amazon.com/AWSEC2/latest/APIReference/OperationList-query-vpc.html'
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_ChangeToVPC.yaml
triggerThreshold: 0
queryPeriod: 1d
alertDetailsOverride:
  alertDisplayNameFormat: AWS VPC change by {{AccountName}} in {{AWSRegion}}
  alertDescriptionFormat: Event {{EventName}} executed by {{AccountName}} from {{SourceIpAddress}}.
id: 65360bb0-8986-4ade-a89d-af3cf44d28aa
queryFrequency: 1d
kind: Scheduled
relevantTechniques:
- T1078
- T1562.007
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP

{
  "$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/65360bb0-8986-4ade-a89d-af3cf44d28aa')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/65360bb0-8986-4ade-a89d-af3cf44d28aa')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Event {{EventName}} executed by {{AccountName}} from {{SourceIpAddress}}.",
          "alertDisplayNameFormat": "AWS VPC change by {{AccountName}} in {{AWSRegion}}"
        },
        "alertRuleTemplateName": "65360bb0-8986-4ade-a89d-af3cf44d28aa",
        "customDetails": {
          "AWSRegion": "AWSRegion",
          "EventName": "EventName",
          "EventSource": "EventSource",
          "RecipientAccountId": "RecipientAccountId"
        },
        "description": "Identifies changes to Amazon VPC(Virtual Private Cloud) settings that can alter network exposure, routing, or access controls.\nThis rule identifies changes to Amazon VPC (Virtual Private Cloud) settings such as new ACL entries, routes, routetable or Gateways. \nAWS VPC API Docs: https://docs.aws.amazon.com/AWSEC2/latest/APIReference/OperationList-query-vpc.html'\n",
        "displayName": "AWSCloudTrail - Changes to Amazon VPC settings",
        "enabled": true,
        "entityMappings": [
          {
            "entityType": "Account",
            "fieldMappings": [
              {
                "columnName": "AccountName",
                "identifier": "Name"
              },
              {
                "columnName": "AccountUPNSuffix",
                "identifier": "UPNSuffix"
              },
              {
                "columnName": "RecipientAccountId",
                "identifier": "CloudAppAccountId"
              }
            ]
          },
          {
            "entityType": "IP",
            "fieldMappings": [
              {
                "columnName": "SourceIpAddress",
                "identifier": "Address"
              }
            ]
          }
        ],
        "OriginalUri": "https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_ChangeToVPC.yaml",
        "query": "let EventNameList = dynamic([\"CreateNetworkAclEntry\",\"CreateRoute\",\"CreateRouteTable\",\"CreateInternetGateway\",\"CreateNatGateway\"]);\nAWSCloudTrail\n| where EventName in~ (EventNameList)\n| where EventSource != \"apigateway.amazonaws.com\"\n| extend UserIdentityArn = iif(isempty(UserIdentityArn), tostring(parse_json(Resources)[0].ARN), UserIdentityArn)\n| extend UserName = tostring(split(UserIdentityArn, '/')[-1])\n| extend AccountName = case( UserIdentityPrincipalid == \"Anonymous\", \"Anonymous\", isempty(UserIdentityUserName), UserName, UserIdentityUserName)\n| extend AccountName = iif(AccountName contains \"@\", tostring(split(AccountName, '@', 0)[0]), AccountName),\n  AccountUPNSuffix = iif(AccountName contains \"@\", tostring(split(AccountName, '@', 1)[0]), \"\")\n| summarize StartTimeUtc = min(TimeGenerated), EndTimeUtc = max(TimeGenerated) by EventName, EventTypeName, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityAccountId, UserIdentityPrincipalid, UserAgent,\nUserIdentityUserName, SessionMfaAuthenticated, SourceIpAddress, AWSRegion, EventSource, AdditionalEventData, ResponseElements\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Low",
        "status": "Available",
        "subTechniques": [
          "T1562.007"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion",
          "PrivilegeEscalation"
        ],
        "techniques": [
          "T1078",
          "T1562"
        ],
        "templateVersion": "1.0.8",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}