  A smart city is a place where existing facilities and services are enhanced
by digital technology to benefit people and companies. The most critical
infrastructures in this city are interconnected. Increased data exchange across
municipal domains aims to manage the essential assets, leading to more
automation in city governance and optimization of the dynamic offered services.
However, no clear guideline or standard exists for modeling these data flows.
As a result, operators, municipalities, policymakers, manufac-turers, solution
providers, and vendors are forced to accept systems with limited scalability
and varying needs. Nonetheless, it is critical to raise awareness about smart
city cybersecurity and implement suitable measures to safeguard citizens'
privacy and security because the cyber threats seem to be well-organized,
diverse, and sophisticated. This study aims to present an overview of cyber
threats, attacks, and countermeasures on the primary domains of smart cities
(smart government, smart mobility, smart environment, smart living, smart
healthcare, smart economy, and smart people) to present information extracted
from state-of-the-art to policymakers to perceive the critical situation and,
at the same time, to be a valuable resource for the scientific community.
