Uzun, EmreParlato, G.Atluri, V.Ferrara, A. L.Vaidya, J.Sural, S.Lorenzi, D.2018-04-122018-04-12201797833196117540302-9743http://hdl.handle.net/11693/37651Conference name: 31st Annual IFIP WG 11.3 Conference, DBSec 2017Date of Conference: July 19-21, 2017Trojan Horse attacks can lead to unauthorized data flows and can cause either a confidentiality violation or an integrity violation. Existing solutions to address this problem employ analysis techniques that keep track of all subject accesses to objects, and hence can be expensive. In this paper we show that for an unauthorized flow to exist in an access control matrix, a flow of length one must exist. Thus, to eliminate unauthorized flows, it is sufficient to remove all one-step flows, thereby avoiding the need for expensive transitive closure computations. This new insight allows us to develop an efficient methodology to identify and prevent all unauthorized flows leading to confidentiality and integrity violations. We develop separate solutions for two different environments that occur in real life, and experimentally validate the efficiency and restrictiveness of the proposed approaches using real data sets. © IFIP International Federation for Information Processing 2017.EnglishAccess controlData transferMalwareAnalysis techniquesData flowKeep track ofReal data setsStep flowTransitive closure computationsTrojan Horse attacksData privacyConference Paper10.1007/978-3-319-61176-1_310.1007/978-3-319-61176-1