基于贝叶斯攻击图的SDN入侵意图识别算法的研究

针对目前已有的软件定义网络（SDN）安全预测方法中未考虑攻击代价以及控制器漏洞对SDN安全所产生的影响,提出了一种基于贝叶斯攻击图的SDN入侵意图识别算法。利用PageRank算法求出设备关键度,并与漏洞价值、攻击成本、攻击收益以及攻击偏好相结合构建攻击图,建立风险评估模型,对入侵路径进行预测。通过实验对比可以看出,所提模型能更准确地预测入侵路径,有效地保证安全预测的准确性,并为SDN的防御提供依据。     

基于攻击图的主机安全评估方法

针对目前主机安全评估方法中无法准确计算主机安全值,忽略攻击图中主机关联性等问题,提出一种基于攻击图的主机安全评估方法.首先,生成主机攻击图,从漏洞自身、时间、环境和操作系统可利用性4个角度量化原子攻击概率并计算主机攻击概率.然后,根据专家先验评估和相关性定权法计算主机资产重要性,依据攻击图中主机间的关联关系计算主机的拓...     

基于攻击图的网络安全分析方法研究

病毒漏洞的大量出现,给网络安全带来了一定的威胁,尤其是DDoS攻击给网络安全敲响了警钟。在安全网络研究方面,攻击图是很好的一种研究方法,它能够给出清晰的结构图,使网络安全人员找到可能的攻击路径,从而重点防范,以减少网络安全事故的发生。论文介绍了这种基于攻击图的网络安全分析方法,最后给出一个系统原型。     

基于贝叶斯网络的攻击图方法在网络安全评估中的应用

随着网络的发展,网络安全评估成为网络维护中不可或缺的组成部分,尽管攻击图、攻击树和其他技术已被广泛地用于预测所有漏洞,但仍然缺少一个有效的手段来量化地分析网络安全.介绍一个新方法构建一个带标记的攻击图,图中的每个节点都被标注了一个概率值用来说明该漏洞被成功利用的可能性,每条边都代表了漏洞间的关联.采用通用漏洞评分系统(CVSS)作为基础计算每个漏洞被利用的概率,采用贝叶斯网络计算累积的概率,并用一些典型场景评估了该方法的有效性和准确性.     

基于专家知识的攻击图生成方法

由于网络规模的不断扩大,独立的漏洞分析已经不能满足安全防护需求。攻击图作为一个新的工具能够清晰表述网络结构,使网络安全人员分析漏洞的相互关联,从而更好地了解网络的漏洞并加以有效的补救,但是传统的攻击图生成方法生成的攻击图会随着网络规模的扩大而复杂度急剧上升。从安全管理者的角度可以采用一种新的生成方法来生成较为简洁的攻击图,这种方法从网络的关键节点出发生成攻击图,可以有效地减少攻击图的规模。     

基于动态概率攻击图的云环境攻击场景构建方法

针对复杂多步攻击检测问题,研究面向云计算环境的攻击场景构建方法.首先,构建了动态概率攻击图模型,设计了概率攻击图更新算法,使之能够随着时空的推移而周期性更新,从而适应弹性、动态性的云计算环境.其次,设计了攻击意图推断算法和最大概率攻击路径推断算法,解决了误报、漏报导致的攻击场景错误、断裂等不确定性问题,保证了攻击场景的...     

基于攻击图模型的网络安全态势评估方法

针对网络攻击出现的大规模、协同、多阶段的特点,提出一种基于攻击图模型的网络安全态势评估方法.首先,结合攻击事件的时空特征融合多源告警数据构建网络攻击行为特征;其次,基于告警信息映射攻击节点,关联多步攻击的路径;再次,在构建攻击图的基础上,结合转移序列构建攻击节点转移概率表,将转移概率引入攻击图中,推断攻击者的攻击意图;...     

一种基于网络会计信息攻击图算法设计方法

网络攻击已成为网络安全技术研究的主要问题,入侵形式的多样性、入侵技术的复杂性使得攻击呈大规模、协同化和多层次趋势发展,网络攻击问题已成为当前研究的热点。通过分析多种网络攻击行为以及工作原理,提出一种基于攻击图的算法,并对其进行深入分析,以用来防范网络攻击问题。     

基于攻击图及蚁群算法的安全评估

攻击图是网络安全分析人员常用的分析工具之一,文章重点研究了基于攻击图模型的系统安全分析架构,并结合攻击难度提出了应用蚁群算法,在攻击图中获取最小关键攻击集的优化解。同时,文章将实验结果与贪婪算法进行了比较,证明了蚁群算法在该应用上是一种高效的优化算法。     

SDN中一种基于熵值检测DDoS攻击的方法

软件定义网络(SDN)是一种新型的网络架构,特点是转发控制分离,可以自定义控制器软件。控制器集中控制是SDN的优点之一,但SDN特性也使得其自然成为分布式拒绝服务攻击(DDo S)的目标,容易造成管理网络功能的失效。文中提出了一种基于熵值的DDo S攻击检测算法,该算法利用控制器集中控制的特点,高效地处理数据包的信息,通过计算熵值,检测DDo S攻击并发出警报。实验表明该方法具有较高的准确度。     

Quantitative method for network security situation based on attack prediction

To predict the attack behaviors accurately and comprehensively as well as to quantify the threat of attack,a quantitative method for network security situation based on attack prediction was proposed.By fusing the situation factors of attacker,defender and network environment,the capability of attacker and the exploitability rate of vulnerability were evaluated utilizing the real-time detected attack events,and the expected time-cost for attack-defense were further calculated.Then an attack prediction algorithm based on the dynamic Bayesian attack graph was designed to infer the follow-up attack actions.At last,the attack threat was quantified as the security risk situation from two levels of the hosts and the overall network.Experimental analysis indicates that the proposed method is suitable for the real adversarial network environment,and is able to predict the occurrence time of attack accurately and quantify the attack threat reasonably.     

基于攻击图模型的网络安全评估研究

介绍了利用攻击图模型方法分析计算机网络攻击行为的基本原理,给出了攻击图生成算法。研究了利用攻击图对网络系统安全性进行风险分析的方法。通过一个虚拟的网络环境对攻击图生成算法和网络系统的安全性分析评估方法进行了验证。     

基于知识图谱的电网安全漏洞扩展攻击图研究

传统电网安全漏洞攻击图存在预测误差大、耗时长的问题,导致电网运行成本较高.为此,提出基于知识图谱的电网安全漏洞扩展攻击图研究方法.建立电网安全漏洞的挖掘关联规则与漏洞判断矩阵,获取出现安全漏洞概率最大的路径;追踪出现安全漏洞的异常数据来源;对电网安全漏洞处拓扑扫描与漏洞扫描,生成电网安全漏洞扩展攻击图.研究结果表明:在...     

Survey on application of attack graph technology

Attack graph technology was a measure to predict the pattern and process used by attacker to compromise the target network,so as to guide defender to take defensive measures and improve network security.The basic component,types of attack graphs and respective advantages and disadvantages of each type were reviewed.The application status of attack graph technology in risk assessment and network hardening,intrusion detection and alarm correlation,and other aspects were introduced.Several kinds of existing attack graph generation and analysis tools were also presented.At last a survey of some challenges and research trends in future research work was provided.     

UDM:NFV-based prevention mechanism against DDoS attack on SDN controller

DDoS attack extensively existed have been mortal threats for the software-defined networking (SDN) controllers and there is no any security mechanism which can prevent them yet.Combining SDN and network function virtualization (NFV),a novel preventing mechanism against DDoS attacks on SDN controller called upfront detection middlebox (UDM) was proposed.The upfront detection middlebox was deployed between SDN switch interfaces and user hosts distributed,and DDoS attack packets were detected and denied.An NFV-based method of implementing the upfront middlebox was put forward,which made the UDM mechanism be economical and effective.A prototype system based on this mechanism was implemented and lots experiments were tested.The experimental results show that the UDM mechanism based on NFV can real-time and effectively detect and prevent against DDoS attacks on SDN controllers.     

Network intrusion intention analysis model based on Bayesian attack graph

Aiming at the problem of ignoring the impact of attack cost and intrusion intention on network security in the current network risk assessment model,in order to accurately assess the target network risk,a method of network intrusion intention analysis based on Bayesian attack graph was proposed.Based on the atomic attack probability calculated by vulnerability value,attack cost and attack benefit,the static risk assessment model was established in combination with the quantitative attack graph of Bayesian belief network,and the dynamic update model of intrusion intention was used to realize the dynamic assessment of network risk,which provided the basis for the dynamic defense measures of attack surface.Experiments show that the model is not only effective in evaluating the overall security of the network,but also feasible in predicting attack paths.     

计算机网络安全评估建模研究

安全性分析研究工作需要把计算机网络与安全相关的系统资源和安全因素抽取出来建立一种面向安全性分析的安全模型。从安全需求的类别、等级和面临的主要威胁出发,分析了系统设备、访问权限、主体连接关系和弱点,从攻击者目的是提升特权的角度对攻击作了形式化的描述。针对计算机系统的安全故障树方法和网络信息系统的攻击图方法应用了这一安全分析建模工作。