AWSCloudTrail - Privilege escalation via CRUD KMS policy

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Id	d7c39e15-997f-49e5-a782-73bf07db8aa5
Rulename	AWSCloudTrail - Privilege escalation via CRUD KMS policy
Description	Detects inline IAM policy updates that grant broad KMS create, read, update, enable/disable, and delete permissions. This pattern can support key management abuse and indicates possible privilege escalation through expanded cloud role capabilities.
Severity	Medium
Tactics	PrivilegeEscalation
Techniques	T1098.003
Required data connectors	AWS
Kind	Scheduled
Query frequency	1d
Query period	1d
Trigger threshold	0
Trigger operator	gt
Source Uri	https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_PrivilegeEscalationViaCRUDKMSPolicy.yaml
Version	1.0.2
Arm template	d7c39e15-997f-49e5-a782-73bf07db8aa5.json

KQL

AWSCloudTrail
| where EventName in ("PutUserPolicy","PutRolePolicy","PutGroupPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
| extend PolicyName = tostring(parse_json(RequestParameters).policyName)
| extend Statement = parse_json(tostring((parse_json(RequestParameters).policyDocument))).Statement
| mvexpand Statement
| extend Action = parse_json(Statement).Action , Effect = tostring(parse_json(Statement).Effect), Resource = tostring(parse_json(Statement).Resource), Condition = tostring(parse_json(Statement).Condition)
| extend Action = tostring(Action)
| where Effect =~ "Allow" and (Action contains "kms:Create" and (Action contains "kms:Get" or Action contains "kms:Describe")  and (Action contains "kms:Disable" or Action contains "kms:Enable") and Action contains "kms:Delete") and Resource == "*" and Condition == ""
| 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]), "")
| distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityArn, UserIdentityUserName

YAML

relevantTechniques:
- T1098.003
description: |
  Detects inline IAM policy updates that grant broad KMS create, read, update, enable/disable, and delete
  permissions. This pattern can support key management abuse and indicates possible privilege escalation through
  expanded cloud role capabilities.
queryFrequency: 1d
kind: Scheduled
id: d7c39e15-997f-49e5-a782-73bf07db8aa5
tactics:
- PrivilegeEscalation
queryPeriod: 1d
alertDetailsOverride:
  alertDescriptionFormat: Detected {{EventName}} Event, updating inline KMS escalation policy {{PolicyName}} in account {{RecipientAccountId}}.
  alertDisplayNameFormat: AWS KMS privilege escalation policy update by {{AccountName}}
version: 1.0.2
triggerThreshold: 0
severity: Medium
triggerOperator: gt
query: |
  AWSCloudTrail
  | where EventName in ("PutUserPolicy","PutRolePolicy","PutGroupPolicy") and isempty(ErrorCode) and isempty(ErrorMessage)
  | extend PolicyName = tostring(parse_json(RequestParameters).policyName)
  | extend Statement = parse_json(tostring((parse_json(RequestParameters).policyDocument))).Statement
  | mvexpand Statement
  | extend Action = parse_json(Statement).Action , Effect = tostring(parse_json(Statement).Effect), Resource = tostring(parse_json(Statement).Resource), Condition = tostring(parse_json(Statement).Condition)
  | extend Action = tostring(Action)
  | where Effect =~ "Allow" and (Action contains "kms:Create" and (Action contains "kms:Get" or Action contains "kms:Describe")  and (Action contains "kms:Disable" or Action contains "kms:Enable") and Action contains "kms:Delete") and Resource == "*" and Condition == ""
  | 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]), "")
  | distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityArn, UserIdentityUserName
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_PrivilegeEscalationViaCRUDKMSPolicy.yaml
customDetails:
  PolicyName: PolicyName
  RecipientAccountId: RecipientAccountId
  UserIdentityArn: UserIdentityArn
  EventName: EventName
name: AWSCloudTrail - Privilege escalation via CRUD KMS policy
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
entityMappings:
- fieldMappings:
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  - columnName: RecipientAccountId
    identifier: CloudAppAccountId
  entityType: Account
- fieldMappings:
  - columnName: SourceIpAddress
    identifier: Address
  entityType: IP
status: Available

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/d7c39e15-997f-49e5-a782-73bf07db8aa5')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/d7c39e15-997f-49e5-a782-73bf07db8aa5')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Detected {{EventName}} Event, updating inline KMS escalation policy {{PolicyName}} in account {{RecipientAccountId}}.",
          "alertDisplayNameFormat": "AWS KMS privilege escalation policy update by {{AccountName}}"
        },
        "alertRuleTemplateName": "d7c39e15-997f-49e5-a782-73bf07db8aa5",
        "customDetails": {
          "EventName": "EventName",
          "PolicyName": "PolicyName",
          "RecipientAccountId": "RecipientAccountId",
          "UserIdentityArn": "UserIdentityArn"
        },
        "description": "Detects inline IAM policy updates that grant broad KMS create, read, update, enable/disable, and delete\npermissions. This pattern can support key management abuse and indicates possible privilege escalation through\nexpanded cloud role capabilities.\n",
        "displayName": "AWSCloudTrail - Privilege escalation via CRUD KMS policy",
        "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_PrivilegeEscalationViaCRUDKMSPolicy.yaml",
        "query": "AWSCloudTrail\n| where EventName in (\"PutUserPolicy\",\"PutRolePolicy\",\"PutGroupPolicy\") and isempty(ErrorCode) and isempty(ErrorMessage)\n| extend PolicyName = tostring(parse_json(RequestParameters).policyName)\n| extend Statement = parse_json(tostring((parse_json(RequestParameters).policyDocument))).Statement\n| mvexpand Statement\n| extend Action = parse_json(Statement).Action , Effect = tostring(parse_json(Statement).Effect), Resource = tostring(parse_json(Statement).Resource), Condition = tostring(parse_json(Statement).Condition)\n| extend Action = tostring(Action)\n| where Effect =~ \"Allow\" and (Action contains \"kms:Create\" and (Action contains \"kms:Get\" or Action contains \"kms:Describe\")  and (Action contains \"kms:Disable\" or Action contains \"kms:Enable\") and Action contains \"kms:Delete\") and Resource == \"*\" and Condition == \"\"\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| distinct TimeGenerated, EventName, PolicyName, SourceIpAddress, RecipientAccountId, AccountName, AccountUPNSuffix, UserIdentityArn, UserIdentityUserName\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [
          "T1098.003"
        ],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "PrivilegeEscalation"
        ],
        "techniques": [
          "T1098"
        ],
        "templateVersion": "1.0.2",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}