Find an AWS IAM user corresponding to an AWS Access Key

find_iam_user.py

# Find the IAM username belonging to the TARGET_ACCESS_KEY
# Useful for finding IAM user corresponding to a compromised AWS credential

# Requirements:
#
# Environmental variables: 
# 		AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY
# python: 
#		boto

import boto.iam

TARGET_ACCESS_KEY = 'TARGET_KEY'

iam = boto.connect_iam()

users = iam.get_all_users('/')['list_users_response']['list_users_result']['users']

def find_key():
	for user in users:
		for key_result in iam.get_all_access_keys(user['user_name'])['list_access_keys_response']['list_access_keys_result']['access_key_metadata']:
			aws_access_key = key_result['access_key_id']
			if aws_access_key == TARGET_ACCESS_KEY:
				print 'Target key belongs to:'
				print 'user : ' + user['user_name']
				return True
	return False

if not find_key():
	print 'Did not find access key (' + TARGET_ACCESS_KEY + ') in ' + str(len(users)) + ' IAM users.'

Nice. Alternatively, here is a way to do this with the aws CLI tools:

AWS_ACCESS_KEY=AKIAIOSFODNN7EXAMPLE
aws --output text iam list-users | awk '{print $NF}' | xargs -P10 -n1 aws --output text iam list-access-keys --user-name | grep $AWS_ACCESS_KEY

If your personal access key (.aws/credentials) does not have iam premissions, the error will show the key owner's user name, which is nice.

I know this dated, but this comes up as a top google search so figured it would be useful to add this here

You can use the IAM get-user call and avoid having to loop through users and their keys. You will either get the user information (and thus the ARN), or the error will specify the ARN (similar to the list-users).

By default the get-user will get the information for the keys used to connect.

aws iam get-user
A client error (AccessDenied) occurred when calling the GetUser operation: User: arn:aws:iam::account:user/username is not authorized to perform: iam:GetUser on resource: arn:aws:iam::account:user/username

or

{
    "User": {
        "UserName": "user",
        "Path": "/",
        "CreateDate": "date",
        "UserId": "ID",
        "Arn": "arn:aws:iam::account:user/username"
    }
}

@mhoglan made my day, cause the script can't find non IAM account ;)

👍

Thanks!

Thanks for doing all the hard work. Adapted for boto3 (w/credit) here: https://gist.github.com/andymotta/9bb9b28da3816fbc469e9057435bf802

Short enhancement by adding loop to run check for every configure AWS profile:

for profile in $(grep -F '[profi' .aws/config | cut -d' ' -f2 | cut -d']' -f1); do
    aws --profile "${profile}" --output text iam list-users | awk '{print $NF}' | xargs -P10 -n1 aws --profile "${profile}" --output text iam list-access-keys --user-name | grep $AWS_ACCESS_KEY
done

Just a heads-up this can be done with a single call using the "get_access_key_last_used" method of the boto3 IAM client.

http://boto3.readthedocs.io/en/latest/reference/services/iam.html#IAM.Client.get_access_key_last_used

Updated with robperc's boto3 suggestion: https://gist.github.com/andymotta/9bb9b28da3816fbc469e9057435bf802#file-updated_find_user_from_access_key-py

For AWS CLI; you can use this one-liner: aws iam get-access-key-last-used --access-key-id $AWS_ACCESS_KEY_ID

Nice. Alternatively, here is a way to do this with the aws CLI tools:

AWS_ACCESS_KEY=AKIAIOSFODNN7EXAMPLE
aws --output text iam list-users | awk '{print $NF}' | xargs -P10 -n1 aws --output text iam list-access-keys --user-name | grep $AWS_ACCESS_KEY

If your personal access key (.aws/credentials) does not have iam premissions, the error will show the key owner's user name, which is nice.

This works perfectly. Thanks @axelabs

For AWS CLI; you can use this one-liner: aws iam get-access-key-last-used --access-key-id $AWS_ACCESS_KEY_ID

Thanks @AnthonyWC for that. it was all I needed 👍