To combat increasingly sophisticated cyber attacks,the security community has proposed and deployed a large body of threat detection approaches to discover malicious behaviors on host systems and attack payloads in ne...To combat increasingly sophisticated cyber attacks,the security community has proposed and deployed a large body of threat detection approaches to discover malicious behaviors on host systems and attack payloads in network traffic.Several studies have begun to focus on threat detection methods based on provenance data of host-level event tracing.On the other side,with the significant development of big data and artificial intelligence technologies,large-scale graph computing has been widely used.To this end,kinds of research try to bridge the gap between threat detection based on host log provenance data and graph algorithm,and propose the threat detection algorithm based on system provenance graph.These approaches usually generate the system provenance graph via tagging and tracking of system events,and then leverage the characteristics of the graph to conduct threat detection and attack investigation.For the purpose of deeply understanding the correctness,effectiveness,and efficiency of different graph-based threat detection algorithms,we pay attention to mainstream threat detection methods based on provenance graphs.We select and implement 5 state-of-the-art threat detection approaches among a large number of studies as evaluation objects for further analysis.To this end,we collect about 40GB of host-level raw log data in a real-world IT environment,and simulate 6 types of cyber attack scenarios in an isolated environment for malicious provenance data to build our evaluation datasets.The crosswise comparison and longitudinal assessment interpret in detail these detection approaches can detect which attack scenarios well and why.Our empirical evaluation provides a solid foundation for the improvement direction of the threat detection approach.展开更多
用户向Web服务组合提供隐私数据时,不同用户有自身的隐私信息暴露需求,服务组合应支持用户隐私需求的可满足性验证.首先提出一种面向服务组合的用户隐私需求规约方法,用户能够定义隐私数据及不同使用情境的敏感度,采用敏感度-信誉度函...用户向Web服务组合提供隐私数据时,不同用户有自身的隐私信息暴露需求,服务组合应支持用户隐私需求的可满足性验证.首先提出一种面向服务组合的用户隐私需求规约方法,用户能够定义隐私数据及不同使用情境的敏感度,采用敏感度-信誉度函数明确可以使用隐私数据的成员服务,简化隐私需求的同时,提高了隐私需求的通用性.为了验证服务组合是否满足用户隐私需求,首先通过隐私数据项依赖图(privacy data item dependency graph,简称PDIDG)描述组合中隐私数据项的依赖关系,然后采用隐私开放工作流网(privacy open workflow net,简称POWFN)构建隐私敏感的服务组合模型,通过需求验证算法验证服务组合是否满足用户隐私需求,从而能够有效防止用户隐私信息的非法直接暴露和间接暴露.最后,通过实例分析说明了该方法的有效性,并对算法性能进行了实验分析.展开更多
基金supported by National Natural Science Foundation of China (No. U1736218)National Key R&D Program of China (No. 2018YFB0804704)partially supported by CNCERT/CC
文摘To combat increasingly sophisticated cyber attacks,the security community has proposed and deployed a large body of threat detection approaches to discover malicious behaviors on host systems and attack payloads in network traffic.Several studies have begun to focus on threat detection methods based on provenance data of host-level event tracing.On the other side,with the significant development of big data and artificial intelligence technologies,large-scale graph computing has been widely used.To this end,kinds of research try to bridge the gap between threat detection based on host log provenance data and graph algorithm,and propose the threat detection algorithm based on system provenance graph.These approaches usually generate the system provenance graph via tagging and tracking of system events,and then leverage the characteristics of the graph to conduct threat detection and attack investigation.For the purpose of deeply understanding the correctness,effectiveness,and efficiency of different graph-based threat detection algorithms,we pay attention to mainstream threat detection methods based on provenance graphs.We select and implement 5 state-of-the-art threat detection approaches among a large number of studies as evaluation objects for further analysis.To this end,we collect about 40GB of host-level raw log data in a real-world IT environment,and simulate 6 types of cyber attack scenarios in an isolated environment for malicious provenance data to build our evaluation datasets.The crosswise comparison and longitudinal assessment interpret in detail these detection approaches can detect which attack scenarios well and why.Our empirical evaluation provides a solid foundation for the improvement direction of the threat detection approach.
文摘用户向Web服务组合提供隐私数据时,不同用户有自身的隐私信息暴露需求,服务组合应支持用户隐私需求的可满足性验证.首先提出一种面向服务组合的用户隐私需求规约方法,用户能够定义隐私数据及不同使用情境的敏感度,采用敏感度-信誉度函数明确可以使用隐私数据的成员服务,简化隐私需求的同时,提高了隐私需求的通用性.为了验证服务组合是否满足用户隐私需求,首先通过隐私数据项依赖图(privacy data item dependency graph,简称PDIDG)描述组合中隐私数据项的依赖关系,然后采用隐私开放工作流网(privacy open workflow net,简称POWFN)构建隐私敏感的服务组合模型,通过需求验证算法验证服务组合是否满足用户隐私需求,从而能够有效防止用户隐私信息的非法直接暴露和间接暴露.最后,通过实例分析说明了该方法的有效性,并对算法性能进行了实验分析.