  Cooperative Intelligent Transportation Systems (C-ITS) enable communications
between vehicles, road-side infrastructures, and road-users to improve users'
safety and to efficiently manage traffic. Most, if not all, of the intelligent
vehicles-to-everything (V2X) applications, often rely on continuous collection
and sharing of sensitive information such as detailed location information
which raises privacy concerns. In this light, a common approach to concealing
the long-term identity of C-ITS vehicles is using multiple temporary
identifiers, called pseudonyms. However, the legacy pseudonyms management
approach is prone to linking attacks. The introduction of 5G network to V2X
offers enhanced location accuracy, better clock synchronisation, improved
modular service-based architecture, and enhanced security and privacy
preservation controls. Motivated by the above enhancements, we study 5G-enabled
pseudonyms for protecting vehicle identity privacy in C-ITS. We highlight the
gaps in the current standards of pseudonyms management. We further provide
recommendations regarding the pseudonyms management life-cycle.
