Security researcher Joshua Long said the Hack Facebook site works indeed. But it is the user who wants to hack other accounts who ends up having his or her own account hacked instead. The site may also collect login details that could later be used to try to hack into the would-be hackers various online accounts (Facebook or otherwise). Once the spammers have your phone number they might also send you text message spam (or sell your number to other spammers)”]
Source: https://informationsecuritybuzz.com/news/facebook-users-warned-vs-hack-facebook-site/