Examples of attacks: An employee receives a call from a person who identifies himself as being from the IT department. The caller explains that some company computers have been infected with a new virus not recognized by the antivirus software that can destroy all files on a computer, and offers to talk the person through some steps to prevent problems. Following this, the caller asks the person to test a software utility that has just been recently upgraded for allowing users to change passwords. The employee is reluctant to refuse, because the caller has just provided help that will supposedly protect the user from a virus. He reciprocates by complying with the caller's request.