Improving Web Application Security: Threats and - CGISecurity

Chapter 3: Threat Modeling 47Threat Modeling PrinciplesThreat modeling should not be a one time only process. It should be an iterativeprocess that starts during the early phases of the design of your application andcontinues throughout the application life cycle. There are two reasons for this. First,it is impossible to identify all of the possible threats in a single pass. Second, becauseapplications are rarely static and need to be enhanced and adapted to suit changingbusiness requirements, the threat modeling process should be repeated as yourapplication evolves.The ProcessFigure 3.1 shows the threat modeling process that you can perform using a six-stageprocess.Note The following process outline can be used for applications that are currently in developmentand for existing applications.Threat Modeling Process1. Identify Assets2. Create an Architecture Overview3. Decompose the Application4. Identify the Threats5. Document the Threats6. Rate the ThreatsFigure 3.1An overview of the threat modeling process