Changes made to AWS CloudTrail logs

let EventNameList = dynamic(["UpdateTrail","DeleteTrail","StopLogging","DeleteFlowLogs","DeleteEventBus"]);
AWSCloudTrail
| where EventName in~ (EventNameList)
| 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
| extend timestamp = StartTimeUtc

triggerOperator: gt
queryFrequency: 1d
description: |
  'Attackers often try to hide their steps by deleting or stopping the collection of logs that could show their activity.
  This alert identifies any manipulation of AWS CloudTrail, Cloudwatch/EventBridge or VPC Flow logs.
  More Information: AWS CloudTrail API: https://docs.aws.amazon.com/awscloudtrail/latest/APIReference/API_Operations.html 
  AWS Cloudwatch/Eventbridge API: https://docs.aws.amazon.com/eventbridge/latest/APIReference/API_Operations.html 
  AWS DelteteFlowLogs API : https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DeleteFlowLogs.html '   
status: Available
kind: Scheduled
triggerThreshold: 0
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
- connectorId: AWSS3
  dataTypes:
  - AWSCloudTrail
version: 1.0.3
queryPeriod: 1d
name: Changes made to AWS CloudTrail logs
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_ClearStopChangeTrailLogs.yaml
id: 610d3850-c26f-4f20-8d86-f10fdf2425f5
tactics:
- DefenseEvasion
severity: Low
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP
query: |
  let EventNameList = dynamic(["UpdateTrail","DeleteTrail","StopLogging","DeleteFlowLogs","DeleteEventBus"]);
  AWSCloudTrail
  | where EventName in~ (EventNameList)
  | 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
  | extend timestamp = StartTimeUtc  

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "workspace": {
      "type": "String"
    }
  },
  "resources": [
    {
      "apiVersion": "2023-02-01-preview",
      "id": "[concat(resourceId('Microsoft.OperationalInsights/workspaces/providers', parameters('workspace'), 'Microsoft.SecurityInsights'),'/alertRules/610d3850-c26f-4f20-8d86-f10fdf2425f5')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/610d3850-c26f-4f20-8d86-f10fdf2425f5')]",
      "properties": {
        "alertRuleTemplateName": "610d3850-c26f-4f20-8d86-f10fdf2425f5",
        "customDetails": null,
        "description": "'Attackers often try to hide their steps by deleting or stopping the collection of logs that could show their activity.\nThis alert identifies any manipulation of AWS CloudTrail, Cloudwatch/EventBridge or VPC Flow logs.\nMore Information: AWS CloudTrail API: https://docs.aws.amazon.com/awscloudtrail/latest/APIReference/API_Operations.html \nAWS Cloudwatch/Eventbridge API: https://docs.aws.amazon.com/eventbridge/latest/APIReference/API_Operations.html \nAWS DelteteFlowLogs API : https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DeleteFlowLogs.html ' \n",
        "displayName": "Changes made to AWS CloudTrail logs",
        "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 Web Services/Analytic Rules/AWS_ClearStopChangeTrailLogs.yaml",
        "query": "let EventNameList = dynamic([\"UpdateTrail\",\"DeleteTrail\",\"StopLogging\",\"DeleteFlowLogs\",\"DeleteEventBus\"]);\nAWSCloudTrail\n| where EventName in~ (EventNameList)\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\n| extend timestamp = StartTimeUtc\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Low",
        "status": "Available",
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion"
        ],
        "templateVersion": "1.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}