Which of the following commands should be used to accomplish the goal?

A mail service company has hired a penetration tester to conduct an enumeration of all user accounts on an SMTP server to identify whether previous staff member accounts are still active.

Which of the following commands should be used to accomplish the goal?
A . VRFY and EXPN
B. VRFY and TURN
C. EXPN and TURN
D. RCPT TO and VRFY

View Answer

Answer: A

Explanation:

Reference: https://hackerone.com/reports/193314