Using Attack Surface Entry Points and Reachability Analysis to Assess the Risk of Software Vulnerability Exploitability

摘要: An unpatched vulnerability can lead to security breaches. When a new is discovered, it needs be assessed so that prioritized. A major challenge in software the assessment of potential risk due exploitability. CVSS metrics have become de facto standard commonly used assess severity vulnerability. The Base Score measures based on exploitability and impact measures. measured three metrics: Access Vector, Authentication, Complexity. However, assign subjective numbers views experts. Two its factors, Vector are same for almost all vulnerabilities. does not specify how third factor, Complexity, measured, hence we do know if considers properties as factor. In this paper, propose an approach assesses two - attack surface entry points reach ability analysis. reachable located one or function called either directly indirectly by points. likelihood point being using damage potential-effort ratio metric presence system calls deemed dangerous. To illustrate proposed method, five reported vulnerabilities Apache HTTP server 1.3.0 been examined at source code level. results show approach, which uses more detailed information, yield different from Score.