A consultant is hired to do physical penetration testing at a large financial company. In the first day of his assessment, the consultant goes to the company`s building dressed like an electrician…

A consultant is hired to do physical penetration testing at a large financial company. In the first day of his assessment, the consultant goes to the company`s building dressed like an electrician and waits in the lobby for an employee to pass through the main access gate, then the consultant follows the employee behind to get into the restricted area. Which type of attack did the consultant perform?