Applying STRIDE Systematically

Effective STRIDE application requires systematic analysis rather than ad-hoc threat identification. Start by decomposing your system into elements—processes, data stores, data flows, and external entities. For each element, consider all six STRIDE categories. This systematic approach ensures comprehensive coverage and reveals threats that might be overlooked in less structured analyses.

Create a STRIDE matrix with system elements as rows and threat categories as columns. For each intersection, ask whether that threat type applies to that element. Can external entities be spoofed? Can data flows be tampered with? Can processes repudiate their actions? This methodical approach transforms STRIDE from a conceptual framework into a practical analysis tool.

Document identified threats with sufficient detail for action. Include the threatened element, applicable STRIDE category, attack scenario, potential impact, and existing controls. This documentation enables prioritization, mitigation planning, and progress tracking. Well-documented STRIDE analyses also serve as valuable references for security reviews and incident response.

Remember that STRIDE is a tool for threat identification, not risk assessment. After identifying threats through STRIDE, you still need to evaluate likelihood and impact to prioritize mitigation efforts. STRIDE tells you what could go wrong; risk assessment tells you what you should worry about most.