AWSCloudTrail - Creating keys with encrypt policy without MFA

let check_actions = AWSCloudTrail
| where EventName in ("CreateKey", "PutKeyPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
| extend state=parse_json(parse_json(replace_string(tostring(parse_json(RequestParameters)['policy']),'\\"','"')).['Statement'])
| mv-expand state
| extend Action= tostring(parse_json(state.['Action'][0])), Effect=tostring(parse_json(state.['Effect'])),
         Principal=tostring(parse_json(state.['Principal']))
| where Action in ("kms:Encrypt", "kms:*") and (Effect == 'Allow') and (Principal has "*")
| distinct AwsEventId;
AWSCloudTrail
| where EventName in ("CreateKey", "PutKeyPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
| 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]), "")
| join kind=inner (check_actions) on AwsEventId
| extend timestamp = TimeGenerated
| project-away AwsEventId1

alertDetailsOverride:
  alertDisplayNameFormat: AWS KMS key creation or policy update by {{AccountName}} without MFA
  alertDescriptionFormat: 'KMS key creation or policy update by {{AccountName}} without MFA resulted in permissive encrypt access. AwsEventId: {{AwsEventId}}'
entityMappings:
- fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
  entityType: Account
- fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
  entityType: IP
id: 454133a7-5427-4a7c-bdc4-0adfa84dda16
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_CreationofEncryptKeysWithoutMFA.yaml
triggerOperator: gt
tactics:
- Impact
kind: Scheduled
requiredDataConnectors:
- dataTypes:
  - AWSCloudTrail
  connectorId: AWS
queryPeriod: 1d
severity: Medium
relevantTechniques:
- T1485
triggerThreshold: 0
version: 1.0.3
customDetails:
  UserIdentityArn: UserIdentityArn
  AwsEventId: AwsEventId
  EventName: EventName
name: AWSCloudTrail - Creating keys with encrypt policy without MFA
status: Available
query: |
  let check_actions = AWSCloudTrail
  | where EventName in ("CreateKey", "PutKeyPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
  | extend state=parse_json(parse_json(replace_string(tostring(parse_json(RequestParameters)['policy']),'\\"','"')).['Statement'])
  | mv-expand state
  | extend Action= tostring(parse_json(state.['Action'][0])), Effect=tostring(parse_json(state.['Effect'])),
           Principal=tostring(parse_json(state.['Principal']))
  | where Action in ("kms:Encrypt", "kms:*") and (Effect == 'Allow') and (Principal has "*")
  | distinct AwsEventId;
  AWSCloudTrail
  | where EventName in ("CreateKey", "PutKeyPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
  | 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]), "")
  | join kind=inner (check_actions) on AwsEventId
  | extend timestamp = TimeGenerated
  | project-away AwsEventId1
description: |
  Identifies AWS KMS key creation or policy changes that allow `kms:Encrypt` or `kms:*` to any principal. This configuration can expose encryption capability outside approved boundaries and should be investigated as overly permissive or malicious.
queryFrequency: 1d

{
  "$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/454133a7-5427-4a7c-bdc4-0adfa84dda16')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/454133a7-5427-4a7c-bdc4-0adfa84dda16')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "KMS key creation or policy update by {{AccountName}} without MFA resulted in permissive encrypt access. AwsEventId: {{AwsEventId}}",
          "alertDisplayNameFormat": "AWS KMS key creation or policy update by {{AccountName}} without MFA"
        },
        "alertRuleTemplateName": "454133a7-5427-4a7c-bdc4-0adfa84dda16",
        "customDetails": {
          "AwsEventId": "AwsEventId",
          "EventName": "EventName",
          "UserIdentityArn": "UserIdentityArn"
        },
        "description": "Identifies AWS KMS key creation or policy changes that allow `kms:Encrypt` or `kms:*` to any principal. This configuration can expose encryption capability outside approved boundaries and should be investigated as overly permissive or malicious.\n",
        "displayName": "AWSCloudTrail - Creating keys with encrypt policy without MFA",
        "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_CreationofEncryptKeysWithoutMFA.yaml",
        "query": "let check_actions = AWSCloudTrail\n| where EventName in (\"CreateKey\", \"PutKeyPolicy\") and isempty(ErrorCode) and isempty(ErrorMessage)\n| extend state=parse_json(parse_json(replace_string(tostring(parse_json(RequestParameters)['policy']),'\\\\\"','\"')).['Statement'])\n| mv-expand state\n| extend Action= tostring(parse_json(state.['Action'][0])), Effect=tostring(parse_json(state.['Effect'])),\n         Principal=tostring(parse_json(state.['Principal']))\n| where Action in (\"kms:Encrypt\", \"kms:*\") and (Effect == 'Allow') and (Principal has \"*\")\n| distinct AwsEventId;\nAWSCloudTrail\n| where EventName in (\"CreateKey\", \"PutKeyPolicy\") and isempty(ErrorCode) and isempty(ErrorMessage)\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| join kind=inner (check_actions) on AwsEventId\n| extend timestamp = TimeGenerated\n| project-away AwsEventId1\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "Impact"
        ],
        "techniques": [
          "T1485"
        ],
        "templateVersion": "1.0.3",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}