AWSCloudTrail - Privilege escalation via CRUD IAM policy

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Id	e20d35a3-4fec-4c8b-81b1-fc33b41990b0
Rulename	AWSCloudTrail - Privilege escalation via CRUD IAM policy
Description	Detects creation of inline IAM policies that grant broad IAM create, read, update, and delete capabilities. This behavior can establish or expand privileged control paths in the account and should be reviewed as potential privilege escalation.
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 Web Services/Analytic Rules/AWS_PrivilegeEscalationViaCRUDIAMPolicy.yaml
Version	1.0.2
Arm template	e20d35a3-4fec-4c8b-81b1-fc33b41990b0.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 "iam:Create" and (Action contains "iam:Get" or Action contains "iam:List")  and Action contains "iam:Update" and Action contains "iam: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
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
name: AWSCloudTrail - Privilege escalation via CRUD IAM policy
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 "iam:Create" and (Action contains "iam:Get" or Action contains "iam:List")  and Action contains "iam:Update" and Action contains "iam: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  
customDetails:
  EventName: EventName
  RecipientAccountId: RecipientAccountId
  PolicyName: PolicyName
  UserIdentityArn: UserIdentityArn
description: |
  Detects creation of inline IAM policies that grant broad IAM create, read, update, and delete capabilities.
  This behavior can establish or expand privileged control paths in the account and should be reviewed as potential
  privilege escalation.  
severity: Medium
triggerOperator: gt
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
kind: Scheduled
id: e20d35a3-4fec-4c8b-81b1-fc33b41990b0
alertDetailsOverride:
  alertDisplayNameFormat: AWS IAM privilege escalation policy update by {{AccountName}}
  alertDescriptionFormat: Detected {{EventName}} Event, updating inline IAM escalation policy {{PolicyName}} in account {{RecipientAccountId}}.
tactics:
- PrivilegeEscalation
triggerThreshold: 0
queryFrequency: 1d
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_PrivilegeEscalationViaCRUDIAMPolicy.yaml
version: 1.0.2
status: Available

ARM