Vulnerability Based Approaches

These approaches consider threats against a software application. Threats are risks of security exploits. For example, threats exist against software applications using the network interface, because someone can intercept data being sent and received through the network interface. Threat based approaches, therefore, use an external perspective, because threats are external to the software application. Assessing the security of an application consists of identifying threats and testing if they can be realized.

• Vulnerability Based Approaches:
These approaches consider vulnerabilities present in the software application. Vulnerability is defined as a state of the system. What differentiates a vulnerable state from any other state is the fact that it is possible to move to an incorrect system state from it [BISH96b]. In other words, vulnerability is a defect which, when exploited, can produce undesirable or incorrect behavior. Vulnerability based approaches, therefore, use an internal perspective to assessing security because vulnerabilities are internal to the software application. Software applications are attacked by exploiting vulnerabilities present in them. Therefore, assessing security can be achieved by identifying vulnerabilities present in the software application.
It is important to note the difference between vulnerability and an exploit. An exploit consists of vulnerability present in the software application and a method used to take advantage of that vulnerability. Thus, an exploit occurs when a method is applied to exercise the vulnerability. For example, the buffer overflow exploit consists of a vulnerability, which is an unbounded buffer; the method used to exercise that vulnerability is to store data larger tha...

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...ality of software security and also its attributes. Some techniques for providing such assurances have been developed in the past, but no single technique has provided a complete solution to the problem. Thus, this thesis will explore the effectiveness of combining two such techniques into a single tool.
The more general purpose of this research is to improve the available methods and life cycle of software testing. Currently, there are a number of fads in software development each with their own buzz words like “extreme” and “agile”. Each of these fads comes with its own testing methodology. However, the majority of them focus on assuring that a system does everything it is supposed to do, that it is complete. There are few available tools that can assure a system’s lack of excess functionality. The goal of this research is to provide a tool that accomplishes both.