Detection rules › Sigma
IAM User Created
Detects when an IAM user creates a new IAM user via CreateUser. This is a common persistence technique where an attacker with compromised credentials creates a backdoor IAM user for continued access even after the originally compromised credentials are rotated.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence | T1136.003 Create Account: Cloud Account |
Event coverage
| Provider | Event |
|---|---|
| AWS-iam | CreateUser |
Rules detecting the same action
Other rules on this platform that filter on the same API call or operation.
- AWS IAM Create User via Assumed Role on EC2 Instance (Elastic)
- AWS IAM S3Browser User or AccessKey Creation (Sigma)
- AWS IAM Sensitive Operations via Lambda Execution Role (Elastic)
- AWS Sensitive IAM Operations Performed via CloudShell (Elastic)
- High-Risk Cross-Cloud User Impersonation (Kusto)
- IAM User Creation Attempt (Sigma)
Rule body yaml
title: IAM User Created
id: 8f3a7b2c-1d4e-5f6a-9b0c-2e3d4f5a6b7c
status: test
description: |
Detects when an IAM user creates a new IAM user via CreateUser.
This is a common persistence technique where an attacker with compromised
credentials creates a backdoor IAM user for continued access even after
the originally compromised credentials are rotated.
references:
- https://attack.mitre.org/techniques/T1136/003/
- https://docs.aws.amazon.com/IAM/latest/APIReference/API_CreateUser.html
- https://hackingthe.cloud/aws/post_exploitation/create_a_console_session_from_iam_credentials/
author: nishikawaakira (@nishikawaakira)
date: 2026-05-03
modified: 2026-05-29
tags:
- attack.persistence
- attack.t1136.003
logsource:
product: aws
service: cloudtrail
detection:
selection:
eventSource: iam.amazonaws.com
eventName: CreateUser
filter:
errorCode|exists: true
condition: selection and not filter
falsepositives:
- Legitimate IAM administrators creating new users
- Automated provisioning systems (Terraform, CloudFormation, SCIM)
level: high
Stages and Predicates
Stage 0: condition
selection and not filterStage 1: selection
selection:
eventSource: iam.amazonaws.com
eventName: CreateUser
Stage 2: not filter
filter:
errorCode|exists: true
Exclusions
Top-level NOT(...) conjuncts: predicates this rule actively suppresses.
| Field | Kind | Excluded values |
|---|---|---|
errorCode | is_not_null |
Indicators
Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.
| Field | Kind | Values |
|---|---|---|
eventName | eq |
|
eventSource | eq |
|