metasploit-framework/documentation/modules/auxiliary/scanner/msmail/onprem_enum.md

OWA (Outlook Webapp) is vulnerable to time-based user enumeration attacks. This module leverages all known, and even some lesser-known services exposed by default Exchange installations to enumerate users. It also targets Office 365 for error-based user enumeration.

• Error-based user enumeration for on premise Exchange services

Note: Currently uses RHOSTS which resolves to an IP which is NOT desired, this is currently being fixed

Verification Steps

• Start msfconsole
• use auxiliary/scanner/msmail/onprem_enum
• set RHOSTS <target>
• set (USERorUSER_FILE`)
• run
• creds

Results should look something like below if valid users were found:

host      origin    service        public  private  realm  private_type
----      ------    -------        ------  -------  -----  ------------
10.1.1.1  10.1.1.1  443/tcp (owa)
10.1.1.1  10.1.1.1  443/tcp (owa)  chris