Computer networks face a variety of cyberattacks.Most network attacks are contagious and destructive,and these types of attacks can be harmful to society and computer network security.Security evaluation is an effecti...Computer networks face a variety of cyberattacks.Most network attacks are contagious and destructive,and these types of attacks can be harmful to society and computer network security.Security evaluation is an effective method to solve network security problems.For accurate assessment of the vulnerabilities of computer networks,this paper proposes a network security risk assessment method based on a Bayesian network attack graph(B_NAG)model.First,a new resource attack graph(RAG)and the algorithm E-Loop,which is applied to eliminate loops in the B_NAG,are proposed.Second,to distinguish the confusing relationships between nodes of the attack graph in the conversion process,a related algorithm is proposed to generate the B_NAG model.Finally,to analyze the reachability of paths in B_NAG,the measuring indexs such as node attack complexity and node state transition are defined,and an iterative algorithm for obtaining the probability of reaching the target node is presented.On this basis,the posterior probability of related nodes can be calculated.A simulation environment is set up to evaluate the effectiveness of the B_NAG model.The experimental results indicate that the B_NAG model is realistic and effective in evaluating vulnerabilities of computer networks and can accurately highlight the degree of vulnerability in a chaotic relationship.展开更多
The network attack profit graph(NAPG)model and the attack profit path predication algorithm are presented herein to cover the shortage of considerations in attacker’s subjective factors based on existing network atta...The network attack profit graph(NAPG)model and the attack profit path predication algorithm are presented herein to cover the shortage of considerations in attacker’s subjective factors based on existing network attack path prediction methods.Firstly,the attack profit is introduced,with the attack profit matrix designed and the attack profit matrix generation algorithm given accordingly.Secondly,a path profit feasibility analysis algorithm is proposed to analyze the network feasibility of realizing profit of attack path.Finally,an opportunity profit path and an optimal profit path are introduced with the selection algorithm and the prediction algorithm designed for accurate prediction of the path.According to the experimental test,the network attack profit path predication algorithm is applicable for accurate prediction of the opportunity profit path and the optimal profit path.展开更多
In order to protect the website and assess the security risk of website, a novel website security risk assessment method is proposed based on the improved Bayesian attack graph(I-BAG) model. First, the Improved Bayesi...In order to protect the website and assess the security risk of website, a novel website security risk assessment method is proposed based on the improved Bayesian attack graph(I-BAG) model. First, the Improved Bayesian attack graph model is established, which takes attack benefits and threat factors into consideration. Compared with the existing attack graph models, it can better describe the website's security risk. Then, the improved Bayesian attack graph is constructed with optimized website attack graph, attack benefit nodes, threat factor nodes and the local conditional probability distribution of each node, which is calculated accordingly. Finally, website's attack probability and risk value are calculated on the level of nodes, hosts and the whole website separately. The experimental results demonstrate that the risk evaluating method based on I-BAG model proposed is a effective way for assessing the website security risk.展开更多
基金This work was partially supported by the National Natural Science Foundation of China(61300216,Wang,H,www.nsfc.gov.cn).
文摘Computer networks face a variety of cyberattacks.Most network attacks are contagious and destructive,and these types of attacks can be harmful to society and computer network security.Security evaluation is an effective method to solve network security problems.For accurate assessment of the vulnerabilities of computer networks,this paper proposes a network security risk assessment method based on a Bayesian network attack graph(B_NAG)model.First,a new resource attack graph(RAG)and the algorithm E-Loop,which is applied to eliminate loops in the B_NAG,are proposed.Second,to distinguish the confusing relationships between nodes of the attack graph in the conversion process,a related algorithm is proposed to generate the B_NAG model.Finally,to analyze the reachability of paths in B_NAG,the measuring indexs such as node attack complexity and node state transition are defined,and an iterative algorithm for obtaining the probability of reaching the target node is presented.On this basis,the posterior probability of related nodes can be calculated.A simulation environment is set up to evaluate the effectiveness of the B_NAG model.The experimental results indicate that the B_NAG model is realistic and effective in evaluating vulnerabilities of computer networks and can accurately highlight the degree of vulnerability in a chaotic relationship.
基金the National Natural Science Foundation of China(61802117)。
文摘The network attack profit graph(NAPG)model and the attack profit path predication algorithm are presented herein to cover the shortage of considerations in attacker’s subjective factors based on existing network attack path prediction methods.Firstly,the attack profit is introduced,with the attack profit matrix designed and the attack profit matrix generation algorithm given accordingly.Secondly,a path profit feasibility analysis algorithm is proposed to analyze the network feasibility of realizing profit of attack path.Finally,an opportunity profit path and an optimal profit path are introduced with the selection algorithm and the prediction algorithm designed for accurate prediction of the path.According to the experimental test,the network attack profit path predication algorithm is applicable for accurate prediction of the opportunity profit path and the optimal profit path.
基金supported by the project of the State Key Program of National Natural Science Foundation of China (No. 90818021)supported by a grant from the national high technology research and development program of China (863program) (No.2012AA012903)
文摘In order to protect the website and assess the security risk of website, a novel website security risk assessment method is proposed based on the improved Bayesian attack graph(I-BAG) model. First, the Improved Bayesian attack graph model is established, which takes attack benefits and threat factors into consideration. Compared with the existing attack graph models, it can better describe the website's security risk. Then, the improved Bayesian attack graph is constructed with optimized website attack graph, attack benefit nodes, threat factor nodes and the local conditional probability distribution of each node, which is calculated accordingly. Finally, website's attack probability and risk value are calculated on the level of nodes, hosts and the whole website separately. The experimental results demonstrate that the risk evaluating method based on I-BAG model proposed is a effective way for assessing the website security risk.
