Threat modeling can help organizations minimize the potential cost and need to rework code while in development or in post-production support. To help make threat modeling a little easier, Microsoft offers a free SDL Threat Modeling Tool that enables non-security subject matter experts to create and analyze threat models by communicating about the security design of their systems, analyzing those designs for potential security issues using a proven methodology and suggesting and managing mitigations for security issues.
Read more here – http://blogs.technet.com/b/security/archive/2012/08/23/microsoft-s-free-security-tools-threat-modeling.aspx?Redirected=true
