  Computer systems process, store and transfer sensitive information which
makes them a valuable asset. Despite the existence of standards such as ISO
27005 for managing information risk, cyber threats are increasing, exposing
such systems to security breaches, and at the same time, compromising users'
privacy. However, threat modelling has also emerged as an alternative to
identify and analyze them, reducing the attack landscape by discarding low-risk
attack vectors, and mitigating high-risk ones. In this work, we introduce a
novel threat-modelling-based approach for risk management, using ISO 27005 as a
baseline for integrating ISO 27001/27002 security controls with privacy
regulations outlined in the European General Data Protection Regulation (GDPR).
In our proposal, risk estimation and mitigation is enhanced by combining STRIDE
and attack trees as a threat modelling strategy. Our approach is applied to an
IoT case study, where different attacks are analyzed to determine their risk
levels and potential countermeasures.
