网络协议安全对于互联网信息安全至关重要。目前主流的网络协议漏洞挖掘技术在安全性能、数据完整性、协议解析和逆向漏洞挖掘等方面还存在缺陷。模糊测试因其自动化程度高且能直接获得漏洞概念验证(Proof of Concept,PoC)的特点,在协...网络协议安全对于互联网信息安全至关重要。目前主流的网络协议漏洞挖掘技术在安全性能、数据完整性、协议解析和逆向漏洞挖掘等方面还存在缺陷。模糊测试因其自动化程度高且能直接获得漏洞概念验证(Proof of Concept,PoC)的特点,在协议安全测试中被广泛使用。然而,针对闭源协议的模糊测试,目前还缺少成熟的解决方案。因此,提出了NASFuzz模糊测试框架,能够对闭源NAS协议(NFS、NAS Find协议)进行漏洞挖掘。首先对闭源协议通信字段进行逆向,形成语法语义合规的模板;其次基于该模板,针对性变异字段中的非保留字段进行变异,生成大量的测试字段对协议进行测试。实验显示,NASFuzz模糊测试框架相比黑盒模糊测试框架BooFuzz,其有效样例生成数量高出70%以上,代码覆盖率提升18%,证明NASFuzz对NAS协议的测试相比传统黑盒测试更充分。展开更多
Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 night...Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 nights of observation,68 Nis and 56 Nas were observed.The seasonal variation of Nis and Nas was also obtained,with the highest occurrence of Nis being in July(43%)and that of Nas being in June(61%).We found that the seasonal variation of Nis is similar to that of Nas and that both occur more frequently in summer than in winter.In addition,we found 23 events in which Nis and Nas occur simultaneously.The average peak altitude of Nas is approximately 1 km higher than that of Nis,and the peak density ratio of Nas to Nis is approximately 5,which is half the density ratio of the two main layers.Additionally,the strength factor for Nas is smaller than that for Nis.Through data analysis of sporadic E layers(Es),we found that Nis and Nas has a significant correlation with Es.The neutralization rates of Ni^(+)/Na^(+)were calculated according to the dissociative recombination reaction of Ni^(+)/Na^(+)and the WACCM-Ni(Whole Atmosphere Community Climate Model of Ni).The production rates of Ni and Na were estimated to be approximately 1:4.4,which is consistent with the density ratio of Nis to Nas.The results showed that the neutralization reaction of Ni+,Na+,and electrons in Es is the main reason for the formation of the Nis layer and the Nas layer.展开更多
文摘网络协议安全对于互联网信息安全至关重要。目前主流的网络协议漏洞挖掘技术在安全性能、数据完整性、协议解析和逆向漏洞挖掘等方面还存在缺陷。模糊测试因其自动化程度高且能直接获得漏洞概念验证(Proof of Concept,PoC)的特点,在协议安全测试中被广泛使用。然而,针对闭源协议的模糊测试,目前还缺少成熟的解决方案。因此,提出了NASFuzz模糊测试框架,能够对闭源NAS协议(NFS、NAS Find协议)进行漏洞挖掘。首先对闭源协议通信字段进行逆向,形成语法语义合规的模板;其次基于该模板,针对性变异字段中的非保留字段进行变异,生成大量的测试字段对协议进行测试。实验显示,NASFuzz模糊测试框架相比黑盒模糊测试框架BooFuzz,其有效样例生成数量高出70%以上,代码覆盖率提升18%,证明NASFuzz对NAS协议的测试相比传统黑盒测试更充分。
基金supported by the Specialized Research Fund for State Key Laboratories,Chinese Meridian Project,the Specialized Research Fund for the State Key Laboratory of Solar Activity and Space Weather,postgraduate Education Reform and Quality Improvement Project of Henan Province(Grant No.YJS2024JD32)Natural Science Foundation Project of Henan Province(Grant No.242300420253)National Natural Science Foundation of China for Young Scientists(Grant No.42504156)funding.
文摘Here we report on simultaneous lidar observations of sporadic Ni(Nis)layers and sporadic Na(Nas)layers in the atmosphere over Yanqing,Beijing(40.42°N,116.02°E)from April 2019 to October 2022.During 343 nights of observation,68 Nis and 56 Nas were observed.The seasonal variation of Nis and Nas was also obtained,with the highest occurrence of Nis being in July(43%)and that of Nas being in June(61%).We found that the seasonal variation of Nis is similar to that of Nas and that both occur more frequently in summer than in winter.In addition,we found 23 events in which Nis and Nas occur simultaneously.The average peak altitude of Nas is approximately 1 km higher than that of Nis,and the peak density ratio of Nas to Nis is approximately 5,which is half the density ratio of the two main layers.Additionally,the strength factor for Nas is smaller than that for Nis.Through data analysis of sporadic E layers(Es),we found that Nis and Nas has a significant correlation with Es.The neutralization rates of Ni^(+)/Na^(+)were calculated according to the dissociative recombination reaction of Ni^(+)/Na^(+)and the WACCM-Ni(Whole Atmosphere Community Climate Model of Ni).The production rates of Ni and Na were estimated to be approximately 1:4.4,which is consistent with the density ratio of Nis to Nas.The results showed that the neutralization reaction of Ni+,Na+,and electrons in Es is the main reason for the formation of the Nis layer and the Nas layer.
