Privilege escalation via CRUD IAM policy

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Id	e20d35a3-4fec-4c8b-81b1-fc33b41990b0
Rulename	Privilege escalation via CRUD IAM policy
Description	Detected usage of AttachUserPolicy/AttachGroupPolicy/AttachRolePolicy by CRUD IAM 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_PrivilegeEscalationViaCRUDIAMPolicy.yaml
Version	1.0.1
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
  | extend timestamp = TimeGenerated

YAML

triggerOperator: gt
queryFrequency: 1d
requiredDataConnectors:
- connectorId: AWS
  dataTypes:
  - AWSCloudTrail
relevantTechniques:
- T1484
entityMappings:
- entityType: Account
  fieldMappings:
  - identifier: Name
    columnName: AccountName
  - identifier: UPNSuffix
    columnName: AccountUPNSuffix
  - identifier: CloudAppAccountId
    columnName: RecipientAccountId
- entityType: IP
  fieldMappings:
  - identifier: Address
    columnName: SourceIpAddress
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
    | extend timestamp = TimeGenerated  
triggerThreshold: 0
OriginalUri: https://github.com/Azure/Azure-Sentinel/blob/master/Solutions/Amazon Web Services/Analytic Rules/AWS_PrivilegeEscalationViaCRUDIAMPolicy.yaml
queryPeriod: 1d
name: Privilege escalation via CRUD IAM policy
status: Available
kind: Scheduled
description: |
    'Detected usage of AttachUserPolicy/AttachGroupPolicy/AttachRolePolicy by CRUD IAM policy. Attackers could use these operations for privilege escalation. Verify these actions with the user.'
id: e20d35a3-4fec-4c8b-81b1-fc33b41990b0
version: 1.0.1
tactics:
- PrivilegeEscalation
severity: Medium

ARM