Leo noticed that attackers have breached his wireless network. they seem to have used a brute-force attack on the wifi protected setup pin to exploit the wap and recover the wpa2 password. what type of attack is this?

It is called a WPS brutal force attack.

Explanation:

Wired and wireless networks are both susceptible to attacks. The wired network, the advantage as a cable connection, is more secure than wireless networks, but wireless network also have security measures like the wifi protected set up (WPS).

WPS is used to connect to a network without passphrase, but with a key combination or a PIN.

Brutal force attacks are used on WPS to forcefully generate the PIN, using a third party software.