This article addresses the reassessment of security threats to the Czech Republic in light of developments in the security environment since 2015. The aim is to update the evaluation of selected types of threats and to reflect their current characteristics, with particular emphasis on their interdependencies and their capacity to generate cascading effects. To achieve this objective, a semi-quantitative risk assessment model is applied and extended by incorporating a cascading effect coefficient. The results of the risk assessment indicate that cyberattacks, pandemics, floods, and hazardous substance releases constitute unacceptable risks, whereas the remaining assessed threats fall within the category of conditionally acceptable risks. The proposed methodological extension enables a more accurate assessment of interconnected threats. The findings may be applied in risk assessment processes within crisis management.