An unauthorized individual enters a building following an employee through the employee entrance after the lunch rush. What type of breach has the individual just performed?

Reverse social engineering involves the attacker positioning themselves as an authority or helper so the victim initiates contact with them, not unauthorized physical entry by following someone.

Tailgating occurs when an unauthorized individual gains physical access to a restricted area by closely following an authorized person through a secured entry point without that person's awareness or approval. Unlike piggybacking, the authorized employee does not knowingly allow or assist the intruder. This is a classic physical social engineering attack exploited during high-traffic periods like lunch rushes.

Piggybacking is similar but requires the authorized employee to be aware of and knowingly allow the unauthorized individual to enter, which is not described in this scenario.

Announced is not a recognized social engineering or physical security breach technique in standard IT security frameworks.