Semantic security: specification and enforcement of semantic policies for security-driven collaborations

Collaborative research can often have demands on finer-grained security that go beyond the authentication-only paradigm as typified by many e-Infrastructure/Grid based solutions. Supporting finer-grained access control is often essential for domains where the specification and subsequent enforcement of authorization policies is needed. The clinical domain is one area in particular where this is so. However it is the case that existing security authorization solutions are fragile, inflexible and difficult to establish and maintain. As a result they often do not meet the needs of real world collaborations where robustness and flexibility of policy specification and enforcement, and ease of maintenance are essential. In this paper we present results of the JISC funded Advanced Grid Authorisation through Semantic Technologies (AGAST) project (www.nesc.ac.uk/hub/projects/agast) and show how semantic-based approaches to security policy specification and enforcement can address many of the limitations with existing security solutions. These are demonstrated into the clinical trials domain through the MRC funded Virtual Organisations for Trials and Epidemiological Studies (VOTES) project (www.nesc.ac.uk/hub/projects/votes) and the epidemiological domain through the JISC funded SeeGEO project (www.nesc.ac.uk/hub/projects/seegeo)

Semantics for incident identification and resolution reports

In order to achieve a safe and systematic treatment of security protocols, organizations release a number of technical briefings describing how to detect and manage security incidents. A critical issue is that this document set may suffer from semantic deficiencies, mainly due to ambiguity or different granularity levels of description and analysis. An approach to face this problem is the use of semantic methodologies in order to provide better Knowledge Externalization from incident protocols management. In this article, we propose a method based on semantic techniques for both, analyzing and specifying (meta)security requirements on protocols used for solving security incidents. This would allow specialist getting better documentation on their intangible knowledge about them.Ministerio de Economía y Competitividad TIN2013-41086-

Investigation of Attitudes Towards Security Behaviors

Cybersecurity attacks have increased as Internet technology has proliferated. Symantec’s 2013 Internet Security Report stated that two out of the top three causes of data breaches in 2012 were attributable to human error (Pelgrin, 2014). This suggests a need to educate end users so that they engage in behaviors that increase their cybersecurity. This study researched how a user’s knowledge affects their engagement in security behaviors. Security behaviors were operationalized into two categories: cyber hygiene and threat response behaviors. A sample of 194 San José State University students were recruited to participate in an observational study. Students completed a card sort, a semantic knowledge quiz, and a survey of their intention to perform security behaviors. A personality inventory was included to see if there would be any effects of personality on security behaviors. Multiple regression was used to see how card sorting and semantic knowledge quiz scores predicted security behaviors, but the results were not significant. Despite this, there was a correlation between cyber hygiene behaviors and threat response behaviors, as well as the Big Five personality traits. The results showed that many of the Big Five personality traits correlated with each other, which is consistent with other studies’ findings. The only personality trait that had a correlation with one of the knowledge measures was neuroticism, in which neuroticism had a negative correlation with the semantic knowledge quiz. Implications for future research are discussed to understand how knowledge, cyber hygiene behaviors, and threat response behaviors relate

Experience in using a typed functional language for the development of a security application

In this paper we present our experience in developing a security application using a typed functional language. We describe how the formal grounding of its semantic and compiler have allowed for a trustworthy development and have facilitated the fulfillment of the security specification.Comment: In Proceedings F-IDE 2014, arXiv:1404.578

Semantic Security and Indistinguishability in the Quantum World

At CRYPTO 2013, Boneh and Zhandry initiated the study of quantum-secure encryption. They proposed first indistinguishability definitions for the quantum world where the actual indistinguishability only holds for classical messages, and they provide arguments why it might be hard to achieve a stronger notion. In this work, we show that stronger notions are achievable, where the indistinguishability holds for quantum superpositions of messages. We investigate exhaustively the possibilities and subtle differences in defining such a quantum indistinguishability notion for symmetric-key encryption schemes. We justify our stronger definition by showing its equivalence to novel quantum semantic-security notions that we introduce. Furthermore, we show that our new security definitions cannot be achieved by a large class of ciphers -- those which are quasi-preserving the message length. On the other hand, we provide a secure construction based on quantum-resistant pseudorandom permutations; this construction can be used as a generic transformation for turning a large class of encryption schemes into quantum indistinguishable and hence quantum semantically secure ones. Moreover, our construction is the first completely classical encryption scheme shown to be secure against an even stronger notion of indistinguishability, which was previously known to be achievable only by using quantum messages and arbitrary quantum encryption circuits.Comment: 37 pages, 2 figure

Chosen-ciphertext security from subset sum

We construct a public-key encryption (PKE) scheme whose security is polynomial-time equivalent to the hardness of the Subset Sum problem. Our scheme achieves the standard notion of indistinguishability against chosen-ciphertext attacks (IND-CCA) and can be used to encrypt messages of arbitrary polynomial length, improving upon a previous construction by Lyubashevsky, Palacio, and Segev (TCC 2010) which achieved only the weaker notion of semantic security (IND-CPA) and whose concrete security decreases with the length of the message being encrypted. At the core of our construction is a trapdoor technique which originates in the work of Micciancio and Peikert (Eurocrypt 2012