The activity described, where a department is not using the company VPN when accessing various company-related services and systems, is an example of Shadow IT. Shadow IT refers to the use of IT systems, devices, software, applications, and services without explicit IT department approval.
Espionage: Involves spying to gather confidential information, not simply bypassing the VPN.
Data exfiltration: Refers to unauthorized transfer of data, which might involve not using a VPN but is more specific to the act of transferring data out of the organization.
Nation-state attack: Involves attacks sponsored by nation-states, which is not indicated in the scenario.
Shadow IT: Use of unauthorized systems and services, which aligns with bypassing the company VPN.