This paper reviews writings already done and published on the topic. The Operating systems covered are Windows Vista, Windows XP, Windows 7 Professional and Windows 8. The categories of Vulnerabilities and Threats are discussed with mechanisms implemented and solutions known.

This report is part of a course towards a Masters degree. Firstly the report discusses Literature review of papers published on Security and on Risk management for online transactions. It involves researching on ways to design the project taking into consideration the models and strategies discussed in course lectures. Secondly the project is implemented and follows by an analysis with regards to security threats and risk management covered in the Literature review.