AWSCloudTrail - Changes to internet facing AWS RDS Database instances

let EventNameList = dynamic(["AuthorizeDBSecurityGroupIngress","CreateDBSecurityGroup","DeleteDBSecurityGroup","RevokeDBSecurityGroupIngress"]);
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, AdditionalEventData, ResponseElements

alertDetailsOverride:
  alertDescriptionFormat: Event {{EventName}} change in RDS security settings by {{AccountName}} from {{SourceIpAddress}}.
  alertDisplayNameFormat: AWS RDS database security change by {{AccountName}} in {{AWSRegion}}
status: Available
queryPeriod: 1d
id: 8c2ef238-67a0-497d-b1dd-5c8a0f533e25
customDetails:
  EventName: EventName
  EventSource: EventSource
  AWSRegion: AWSRegion
  EventType: EventTypeName
  UserAgent: UserAgent
version: 1.0.5
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_ChangeToRDSDatabase.yaml
tactics:
- Persistence
- PrivilegeEscalation
- DefenseEvasion
description: |
  Identifies AWS CloudTrail events associated with changes to Amazon RDS database security groups and database
  security group ingress rules, which may indicate unauthorized modification of internet-facing RDS access. Validate whether
  the change was authorized and consistent with change control policy.
  RDS API Reference Docs: https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_Operations.html
relevantTechniques:
- T1098.001
- T1562.007
queryFrequency: 1d
triggerThreshold: 0
kind: Scheduled
name: AWSCloudTrail - Changes to internet facing AWS RDS Database instances
query: |
  let EventNameList = dynamic(["AuthorizeDBSecurityGroupIngress","CreateDBSecurityGroup","DeleteDBSecurityGroup","RevokeDBSecurityGroupIngress"]);
  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, AdditionalEventData, ResponseElements
requiredDataConnectors:
- dataTypes:
  - AWSCloudTrail
  connectorId: AWS
- dataTypes:
  - AWSCloudTrail
  connectorId: AWSS3
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP
triggerOperator: gt
severity: Low

{
  "$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/8c2ef238-67a0-497d-b1dd-5c8a0f533e25')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/8c2ef238-67a0-497d-b1dd-5c8a0f533e25')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Event {{EventName}} change in RDS security settings by {{AccountName}} from {{SourceIpAddress}}.",
          "alertDisplayNameFormat": "AWS RDS database security change by {{AccountName}} in {{AWSRegion}}"
        },
        "alertRuleTemplateName": "8c2ef238-67a0-497d-b1dd-5c8a0f533e25",
        "customDetails": {
          "AWSRegion": "AWSRegion",
          "EventName": "EventName",
          "EventSource": "EventSource",
          "EventType": "EventTypeName",
          "UserAgent": "UserAgent"
        },
        "description": "Identifies AWS CloudTrail events associated with changes to Amazon RDS database security groups and database\nsecurity group ingress rules, which may indicate unauthorized modification of internet-facing RDS access. Validate whether\nthe change was authorized and consistent with change control policy.\nRDS API Reference Docs: https://docs.aws.amazon.com/AmazonRDS/latest/APIReference/API_Operations.html\n",
        "displayName": "AWSCloudTrail - Changes to internet facing AWS RDS Database instances",
        "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_ChangeToRDSDatabase.yaml",
        "query": "let EventNameList = dynamic([\"AuthorizeDBSecurityGroupIngress\",\"CreateDBSecurityGroup\",\"DeleteDBSecurityGroup\",\"RevokeDBSecurityGroupIngress\"]);\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, UserIdentityUserName, SessionMfaAuthenticated, SourceIpAddress, AWSRegion, EventSource, AdditionalEventData, ResponseElements\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Low",
        "status": "Available",
        "subTechniques": [
          "T1098.001",
          "T1562.007"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "DefenseEvasion",
          "Persistence",
          "PrivilegeEscalation"
        ],
        "techniques": [
          "T1098",
          "T1562"
        ],
        "templateVersion": "1.0.5",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}