AppSec Europe 2014

Threat Modeling is a software design analysis method that looks for security weaknesses by juxtaposing software design views against a set of attackers. 

Software engineers and security practitioners at Intuit have been practicing Threat Modeling in various ways for years. Intuit has used a Threat Model methodology based on STRIDE. The approach had many advantages, but also some drawbacks. Some of the drawbacks included amount of time required to translate the information from development (generating the Data Flow Diagrams) and difficulty in modeling different threat agents. 

Intuit and Cigital unified their two Threat Modeling methodologies to produce an approach that satisfies various stakeholders at Intuit. The result was what is called Unified Threat Modeling, an approach that consists of identifying assets and attacker profiles, and documenting and suggesting a list of controls. It works for software architecture and system deployments (using System Threat Modeling approach) as well as for interaction between different software and system components (via Protocol Threat Modeling approach).