AWSCloudTrail - Privilege escalation via CloudFormation policy

Back


Id	719d5204-10ab-4b1f-aee1-da7326750260
Rulename	AWSCloudTrail - Privilege escalation via CloudFormation policy
Description	Detects creation of inline IAM policies with CloudFormation and IAM permissions associated with privilege escalation pathways, including iam:PassRole plus stack creation capabilities. This pattern can enable indirect elevation and should be investigated for unauthorized policy changes.
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_PrivilegeEscalationViaCloudFormationPolicy.yaml
Version	1.0.2
Arm template	719d5204-10ab-4b1f-aee1-da7326750260.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 has "iam:*" or Action has "iam:PassRole") and Action has "cloudformation:*") or ((Action has "iam:*" or Action has "iam:PassRole") and Action contains "cloudformation:DescribeStacks" and Action contains "cloudformation:CreateStack") or ((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "cloudformation:Describe*" and Action contains "cloudformation:Create*")) 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

triggerThreshold: 0
triggerOperator: gt
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon%20Web%20Services/Analytic%20Rules/AWS_PrivilegeEscalationViaCloudFormationPolicy.yaml
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
id: 719d5204-10ab-4b1f-aee1-da7326750260
relevantTechniques:
- T1098.003
alertDetailsOverride:
  alertDisplayNameFormat: AWS CloudFormation privilege escalation policy update by {{AccountName}}
  alertDescriptionFormat: Detected {{EventName}} Event, updating inline CloudFormation escalation policy {{PolicyName}} in account {{RecipientAccountId}}.
entityMappings:
- fieldMappings:
  - columnName: AccountName
    identifier: Name
  - columnName: AccountUPNSuffix
    identifier: UPNSuffix
  - columnName: RecipientAccountId
    identifier: CloudAppAccountId
  entityType: Account
- fieldMappings:
  - columnName: SourceIpAddress
    identifier: Address
  entityType: IP
version: 1.0.2
severity: Medium
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 has "iam:*" or Action has "iam:PassRole") and Action has "cloudformation:*") or ((Action has "iam:*" or Action has "iam:PassRole") and Action contains "cloudformation:DescribeStacks" and Action contains "cloudformation:CreateStack") or ((Action contains "iam:*" or Action contains "iam:PassRole") and Action contains "cloudformation:Describe*" and Action contains "cloudformation:Create*")) 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 with CloudFormation and IAM permissions associated with privilege
  escalation pathways, including iam:PassRole plus stack creation capabilities. This pattern can enable indirect
  elevation and should be investigated for unauthorized policy changes.
status: Available
customDetails:
  PolicyName: PolicyName
  EventName: EventName
  UserIdentityArn: UserIdentityArn
  RecipientAccountId: RecipientAccountId
queryFrequency: 1d
kind: Scheduled
name: AWSCloudTrail - Privilege escalation via CloudFormation policy
queryPeriod: 1d
tactics:
- PrivilegeEscalation

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/719d5204-10ab-4b1f-aee1-da7326750260')]",
      "kind": "Scheduled",
      "name": "[concat(parameters('workspace'),'/Microsoft.SecurityInsights/719d5204-10ab-4b1f-aee1-da7326750260')]",
      "properties": {
        "alertDetailsOverride": {
          "alertDescriptionFormat": "Detected {{EventName}} Event, updating inline CloudFormation escalation policy {{PolicyName}} in account {{RecipientAccountId}}.",
          "alertDisplayNameFormat": "AWS CloudFormation privilege escalation policy update by {{AccountName}}"
        },
        "alertRuleTemplateName": "719d5204-10ab-4b1f-aee1-da7326750260",
        "customDetails": {
          "EventName": "EventName",
          "PolicyName": "PolicyName",
          "RecipientAccountId": "RecipientAccountId",
          "UserIdentityArn": "UserIdentityArn"
        },
        "description": "Detects creation of inline IAM policies with CloudFormation and IAM permissions associated with privilege\nescalation pathways, including iam:PassRole plus stack creation capabilities. This pattern can enable indirect\nelevation and should be investigated for unauthorized policy changes.\n",
        "displayName": "AWSCloudTrail - Privilege escalation via CloudFormation 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_PrivilegeEscalationViaCloudFormationPolicy.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 has \"iam:*\" or Action has \"iam:PassRole\") and Action has \"cloudformation:*\") or ((Action has \"iam:*\" or Action has \"iam:PassRole\") and Action contains \"cloudformation:DescribeStacks\" and Action contains \"cloudformation:CreateStack\") or ((Action contains \"iam:*\" or Action contains \"iam:PassRole\") and Action contains \"cloudformation:Describe*\" and Action contains \"cloudformation:Create*\")) 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"
    }
  ]
}