Detection rules › Sigma
AWS IAM S3Browser User or AccessKey Creation
Detects S3 Browser utility creating IAM User or AccessKey.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Initial Access | T1078.004 Valid Accounts: Cloud Accounts |
| Execution | T1059.009 Command and Scripting Interpreter: Cloud API |
| Persistence | T1078.004 Valid Accounts: Cloud Accounts |
| Privilege Escalation | T1078.004 Valid Accounts: Cloud Accounts |
| Stealth | T1078.004 Valid Accounts: Cloud Accounts |
Event coverage
| Provider | Event |
|---|---|
| AWS-iam | CreateAccessKey |
| AWS-iam | CreateUser |
Rules detecting the same action
Other rules on this platform that filter on the same API call or operation.
- AWS IAM Backdoor Users Keys (Sigma)
- AWS IAM Create User via Assumed Role on EC2 Instance (Elastic)
- AWS IAM Sensitive Operations via Lambda Execution Role (Elastic)
- AWS IAM User Created Access Keys For Another User (Elastic)
- AWS Sensitive IAM Operations Performed via CloudShell (Elastic)
- AWS User API Key Created (Panther)
- High-Risk Cross-Cloud User Impersonation (Kusto)
- IAM Access Key Created (Sigma)
Rule body yaml
title: AWS IAM S3Browser User or AccessKey Creation
id: db014773-d9d9-4792-91e5-133337c0ffee
status: test
description: Detects S3 Browser utility creating IAM User or AccessKey.
references:
- https://permiso.io/blog/s/unmasking-guivil-new-cloud-threat-actor
author: daniel.bohannon@permiso.io (@danielhbohannon)
date: 2023-05-17
tags:
- attack.privilege-escalation
- attack.execution
- attack.persistence
- attack.initial-access
- attack.stealth
- attack.t1059.009
- attack.t1078.004
logsource:
product: aws
service: cloudtrail
detection:
selection:
eventSource: 'iam.amazonaws.com'
eventName:
- 'CreateUser'
- 'CreateAccessKey'
userAgent|contains: 'S3 Browser'
condition: selection
falsepositives:
- Valid usage of S3 Browser for IAM User and/or AccessKey creation
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
eventSource: 'iam.amazonaws.com'
eventName:
- 'CreateUser'
- 'CreateAccessKey'
userAgent|contains: 'S3 Browser'
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 |
|
userAgent | match |
|