To make Hiring Manager access even more secure you can set up an SMS verification.

To do that, go to the Users -> Hiring Managers and click on the profile of the Hiring Manager:

Just fill in the Hiring Manager's phone number field and select SMS verification:

When the SMS verification field is checked, the Mobile phone field becomes a required field and you cannot save the profile without filling it in.

In order to open the candidate's shared profile, the Hiring Manager will be asked to fill the SMS code field and then they be redirected to the candidate's profile.