AWSCloudTrail - Privilege escalation via CRUD DynamoDB policy

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Id	b9be2aa6-911d-4131-8658-d2a537ed49f4
Rulename	AWSCloudTrail - Privilege escalation via CRUD DynamoDB policy
Description	Detects creation of inline IAM policies that grant broad DynamoDB create, read, update, and delete permissions. Attackers may use this access expansion to manipulate data stores and escalate influence across cloud workloads.
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_PrivilegeEscalationviaCRUDDynamoDB.yaml
Version	1.0.2
Arm template	b9be2aa6-911d-4131-8658-d2a537ed49f4.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 "dynamodb:Create" or Action contains "dynamodb:Put") and (Action contains "dynamodb:Describe" or Action contains "dynamodb:Get" or Action contains "dynamodb:Scan")  and Action contains "dynamodb:Update" and Action contains "dynamodb: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

entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
name: AWSCloudTrail - Privilege escalation via CRUD DynamoDB policy
kind: Scheduled
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_PrivilegeEscalationviaCRUDDynamoDB.yaml
triggerOperator: gt
status: Available
queryPeriod: 1d
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
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 "dynamodb:Create" or Action contains "dynamodb:Put") and (Action contains "dynamodb:Describe" or Action contains "dynamodb:Get" or Action contains "dynamodb:Scan")  and Action contains "dynamodb:Update" and Action contains "dynamodb: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
description: |
  Detects creation of inline IAM policies that grant broad DynamoDB create, read, update, and delete permissions.
  Attackers may use this access expansion to manipulate data stores and escalate influence across cloud workloads.
severity: Medium
id: b9be2aa6-911d-4131-8658-d2a537ed49f4
customDetails:
  UserIdentityArn: UserIdentityArn
  EventName: EventName
  PolicyName: PolicyName
  RecipientAccountId: RecipientAccountId
triggerThreshold: 0
queryFrequency: 1d
alertDetailsOverride:
  alertDescriptionFormat: Detected {{EventName}} Event, updating inline DynamoDB escalation policy {{PolicyName}} in account {{RecipientAccountId}}.
  alertDisplayNameFormat: AWS DynamoDB privilege escalation policy update by {{AccountName}}
version: 1.0.2
relevantTechniques:
- T1098.003

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/b9be2aa6-911d-4131-8658-d2a537ed49f4')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/b9be2aa6-911d-4131-8658-d2a537ed49f4')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Detected {{EventName}} Event, updating inline DynamoDB escalation policy {{PolicyName}} in account {{RecipientAccountId}}.",
          "alertDisplayNameFormat": "AWS DynamoDB privilege escalation policy update by {{AccountName}}"
        },
        "alertRuleTemplateName": "b9be2aa6-911d-4131-8658-d2a537ed49f4",
        "customDetails": {
          "EventName": "EventName",
          "PolicyName": "PolicyName",
          "RecipientAccountId": "RecipientAccountId",
          "UserIdentityArn": "UserIdentityArn"
        },
        "description": "Detects creation of inline IAM policies that grant broad DynamoDB create, read, update, and delete permissions.\nAttackers may use this access expansion to manipulate data stores and escalate influence across cloud workloads.\n",
        "displayName": "AWSCloudTrail - Privilege escalation via CRUD DynamoDB 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_PrivilegeEscalationviaCRUDDynamoDB.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 \"dynamodb:Create\" or Action contains \"dynamodb:Put\") and (Action contains \"dynamodb:Describe\" or Action contains \"dynamodb:Get\" or Action contains \"dynamodb:Scan\")  and Action contains \"dynamodb:Update\" and Action contains \"dynamodb: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"
    }
  ]
}