Privilege escalation via CRUD KMS policy

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Id	d7c39e15-997f-49e5-a782-73bf07db8aa5
Rulename	Privilege escalation via CRUD KMS policy
Description	Detected usage of AttachUserPolicy/AttachGroupPolicy/AttachRolePolicy by CRUD KMS policy. Attackers could use these operations for privilege escalation. Verify these actions with the user.
Severity	Medium
Tactics	PrivilegeEscalation
Techniques	T1484
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 Web Services/Analytic Rules/AWS_PrivilegeEscalationViaCRUDKMSPolicy.yaml
Version	1.0.1
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
| extend timestamp = TimeGenerated

YAML

requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
status: Available
relevantTechniques:
- T1484
queryFrequency: 1d
id: d7c39e15-997f-49e5-a782-73bf07db8aa5
name: Privilege escalation via CRUD KMS policy
severity: Medium
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_PrivilegeEscalationViaCRUDKMSPolicy.yaml
queryPeriod: 1d
entityMappings:
- fieldMappings:
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  - columnName: RecipientAccountId
    identifier: CloudAppAccountId
  entityType: Account
- fieldMappings:
  - columnName: SourceIpAddress
    identifier: Address
  entityType: IP
description: |
    'Detected usage of AttachUserPolicy/AttachGroupPolicy/AttachRolePolicy by CRUD KMS policy. Attackers could use these operations for privilege escalation. Verify these actions with the user.'
triggerThreshold: 0
tactics:
- PrivilegeEscalation
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
  | extend timestamp = TimeGenerated  
kind: Scheduled
triggerOperator: gt
version: 1.0.1

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": {
        "alertRuleTemplateName": "d7c39e15-997f-49e5-a782-73bf07db8aa5",
        "customDetails": null,
        "description": "'Detected usage of AttachUserPolicy/AttachGroupPolicy/AttachRolePolicy by CRUD KMS policy. Attackers could use these operations for privilege escalation. Verify these actions with the user.'\n",
        "displayName": "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 Web Services/Analytic Rules/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| extend timestamp = TimeGenerated\n",
        "queryFrequency": "P1D",
        "queryPeriod": "P1D",
        "severity": "Medium",
        "status": "Available",
        "subTechniques": [],
        "suppressionDuration": "PT1H",
        "suppressionEnabled": false,
        "tactics": [
          "PrivilegeEscalation"
        ],
        "techniques": [
          "T1484"
        ],
        "templateVersion": "1.0.1",
        "triggerOperator": "GreaterThan",
        "triggerThreshold": 0
      },
      "type": "Microsoft.OperationalInsights/workspaces/providers/alertRules"
    }
  ]
}