  Recently security researchers have started to look into automated generation
of attack trees from socio-technical system models. The obvious next step in
this trend of automated risk analysis is automating the selection of security
controls to treat the detected threats. However, the existing socio-technical
models are too abstract to represent all security controls recommended by
practitioners and standards. In this paper we propose an attack-defence model,
consisting of a set of attack-defence bundles, to be generated and maintained
with the socio-technical model. The attack-defence bundles can be used to
synthesise attack-defence trees directly from the model to offer basic
attack-defence analysis, but also they can be used to select and maintain the
security controls that cannot be handled by the model itself.
