Following the attack modelling activity ongoing within the Cigré working group D2.31 on “Security architecture principles for digital systems in Electric Power Utilities (EPUs)”, this paper evaluates the capabilities of CySeMoL (Cyber Security Modelling Language). The CySeMoL methodology is applied to describe the grid ICT architecture (networks, operating systems, services, protocols, data flows), the security measures and the source and the target of the attack. The CySeMoL modelling approach is based on the attack graph formalism and provides justifiable quantitative estimates on the likelihood that different attack paths will be successful. In this paper CySeMoL will be used for estimating the likelihood of certain attack processes affecting the Voltage Control functions, including attacks caused by the remote maintenance procedures on the Voltage Control devices. Starting with the description of a Voltage Control function architecture as a representative use case of future smart grids, the paper focusses on the application of CySeMoL to the sample case aimed at the evaluation of the adequacy of the tool to the smart grid sector.