Restrict public S3 buckets with WRITE permissions

This workflow looks at all of the public S3 buckets in a given account and restricts those that provide 'WRITE' access.

It evaluates all buckets for a grant that includes:

• Group containing "http://acs.amazonaws.com/groups/global/AllUsers"
• Permission containing "WRITE"

These buckets will be restricted to be 'private'.

Prerequisites

Before you run this workflow, you will need the following:

• An AWS account.
• An AWS IAM user with permissions to list and modify S3 buckets (if not run in dry run mode).
• One or more S3 buckets that are public and provide 'WRITE' access.

Run the workflow

Follow these steps to run the workflow:
1. Add your AWS credentials as a Connection:

• Click Setup
• Find the Connection named my-aws-account and click Edit(✎). Use the following values:
  • KEY: ACCESS KEY ID
  • VALUE: Enter your AWS access key id associated with the account
  • KEY: SECRET ACCESS KEY
  • VALUE: Enter your AWS secret access key associated with the account
• Click Save
  

2. Click Run workflow and wait for the workflow run page to appear.

3. Supply following parameters to the modal:

   • KEY: dryRun
   • VALUE: True if you don't want to perform actual WRITE operations

4. Warning: If you run the workflow with the dryRun parameter set to false, buckets not in compliance with this workflow policy will immediately be modified to be 'private'.

Run the workflow on a schedule

Follow these steps to run this workflow on a schedule:

• Un-comment out the Trigger block in the workflow file:

TIP: If you're using the Relay code editor, highlight the triggers section and type ⌘ + / (Mac) or Ctrl + / (Windows) to uncomment.

# triggers:
# - name: schedule
#   source:
#     type: schedule
#     schedule: '0 * * * *'
#   binding:
#     parameters:
#       dryRun: true

• Configure the schedule trigger:
  • Supply the run interval in cron format.
• Configure the following parameter bindings:
  • Specify whether dryRun should be set to true or false.
• Click Save changes