title: AWS EC2 Download Userdata
id: 26ff4080-194e-47e7-9889-ef7602efed0c
status: experimental
author: faloker
date: 2020/02/11
description: Detects bulk downloading of User Data associated with AWS EC2 instances. Instance User Data may include installation scripts and hard-coded secrets for deployment.
references:
    - https://github.com/RhinoSecurityLabs/pacu/blob/master/modules/ec2__download_userdata/main.py#L24
logsource:
    service: cloudtrail
detection:
    selection_source:
        - eventSource: ec2.amazonaws.com
    selection_requesttype:
        - requestParameters.attribute: userData
    selection_eventname:
        - eventName: DescribeInstanceAttribute
    timeframe: 30m
    condition: all of them | count() > 10
level: medium
falsepositives:
    - Assets management software like device42
tags:
    - attack.t1020