Azure services are available at specific domains and subdomains. We can enumerate services by finding subdomains.
Example: https://ppbackup.blob.core.windows.net/
MicroBurst
MicroBurst is a useful tool for security assessment for Azure. It uses Az, AzureAD, AzurRM ans MSOL tools and additional REST API calls.
Import-Module MicroBurst.psm1
Enumerate Subdomains:
Invoke-EnumerateAzureSubDomains -Base pp -Verbose
VERBOSE: Found pp.onmicrosoft.com
VERBOSE: Found pp.onmicrosoft.com
VERBOSE: Found pp.onmicrosoft.com
VERBOSE: Found pp.mail.protection.outlook.com
VERBOSE: Found pp.mail.protection.outlook.com
VERBOSE: Found pp.mail.protection.outlook.com