Find the IAM username belonging to the TARGET_ACCESS_KEY

find_iam_user.py

#!/usr/bin/env python
# Find the IAM username belonging to the TARGET_ACCESS_KEY
# Useful for finding IAM user corresponding to a compromised AWS credential
# Usage:
# 		find_iam_user AWS_ACCESS_KEY_ID
# Requirements:
#
# Environmental variables: 
# 		AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY
# python: 
#		boto

import boto.iam
import sys

if len(sys.argv) == 1:
	print 'Usage: \n find_iam_user AWS_ACCESS_KEY_ID'
	exit(1)

TARGET_ACCESS_KEY = sys.argv[1] 

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 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.'

@spenserpothier I've forked and updated this gist to search more than 100 users https://gist.github.com/zxjinn/1693a7b4623c4cd25b6d