Attacking MS Exchange Web Interfaces

During External Penetration Testing, I often see MS Exchange on the perimeter:

Examples of MS Exchange web interfaces

Exchange is basically a mail server that supports a bunch of Microsoft protocols. It’s usually located on subdomains named autodiscover, mx, owa or mail, and it can also be detected by existing /owa/, /ews/, /ecp/, /oab/, /autodiscover/, /Microsoft-Server-ActiveSync/, /rpc/, /powershell/ endpoints on the web server.

The knowledge about how to attack Exchange is crucial for every penetration testing team. If you found yourself choosing between a non-used website on a shared hosting and a MS Exchange, only the latter could guide you inside.

In this article, I’ll cover all the available techniques for attacking MS Exchange web interfaces and introduce a new technique and a new tool to connect to MS Exchange from the Internet and extract arbitrary Active Directory records, which are also known as LDAP records.

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