In this article, a modeling process is defined to address challenges in analyzing attack scenarios and mitigating vulnerabilities in networked environments. Known system vulnerability data, system configuration data, and vulnerability scanner results are considered to create exploitation graphs (egraphs) that are used to represent attack scenarios. Experiments carried out in a cluster computing environment showed the usefulness of proposed techniques in providing in-depth attack scenario analyses for security engineering. Critical vulnerabilities can be identified by employing graph algorithms. Several factors were used to measure the difficulty in executing an attack. A cost/benefit analysis was used for more accurate quantitative analysis of attack scenarios.The authors also show how the attack scenario analyses better help deployment of security products and design of network topologies.