Network vulnerability can lead to right-variation. From the view of how an attacker uses the vulnerabilities to achieve the unauthorized right of the destination entity, this paper models the vulnerabilities which lead to right-variation and introduces the concept of take rule and vulnerability right-variation rule. Based on the constructed right-variation model and the rules, the right-variation road closure can be achieved by using the vulnerability right-variation algorithm. A vulnerable network is modeled as the study case and it shows the effectiveness of the approach.