A technician receives a call from a user who is on vacation.

Logging into a user's account without their explicit permission is a violation of the acceptable use policy, which outlines the rules and regulations by which a user must abide while using a computer system. By logging into the user's account without their permission, the technician would be violating this policy. Additionally, this action could be seen as a breach of confidentiality, as the technician would have access to information that should remain confidential.