In certain critical cases the data flow between business departments in banking organizations has to respect security policies known as Chinese Wall or Bell–La Padula. We show that these policies can be represented by formal requirements and constraints in first-order logic. By additionally providing a formal model for the flow of data between business departments we demonstrate how security po...

The development of third-party hosting, IT outsourcing, service clouds, etc. raises important security concerns. It would be safer to encrypt critical data hosted by a third-parity, but meanwhile, the database should be able to process queries on encrypted data. Many research works have been developed to support search query processing on encrypted data, including the order preserving encryptio...

Order-preserving encryption (OPE) and order-revealing encryption (ORE) are among the core ingredients for encrypted database (EDB) systems as secure cloud storage. In this work, we study the leakage of OPE and ORE and their forward security. We propose generic yet powerful file-injection attacks (FIAs) on OPE/ORE, aimed at the situations of possessing order by and range queries. The FIA schemes...

At ASIACRYPT 2014, Bilgin et al. describe higher-order threshold implementations: a masking countermeasure claiming resistance against higher-order differential power analysis attacks. In this note, we point out that higher-order threshold implementations do not necessarily provide higher-order security. We give as counterexamples two concrete higher-order threshold implementations that exhibit...

The current higher education, both distance education and traditional campus courses, relies more and more on modern information and communication technologies (ICT). The use of computer systems and networks results in a wide range of security issues that must be dealt with in order to create a safe learning environment. In this work, we study the security status within Swedish Net University, ...

Merkle Cryptosystem (MC) is the first cryptosystem which introduces general concept of the public key cryptography. In this paper, we propose Improved Merkle Cryptosystem (IMC), which has significant security advantages over both MC and a variant of MC (VMC). In IMC, cryptographic hash functions and a new puzzle structure are used together in order to increase the security of MC and VMC. The ke...

Order preserving encryption (OPE) is a kind of encryption designed to support searches on ciphertexts. OPE encrypts plaintexts to ciphertexts with the same order, making it possible to efficiently compare ciphertexts without decryption. Because of its efficiency, OPE has been used in systems aimed at practical use. However, even though many OPE schemes have been proposed, all suffer from securi...

Even though Privacy concerns and security concerns are acknowledged as separate constructs, many studies argue that they are related or, even worse, confused. Hence, this study clarifies the nuances between privacy and security concerns, and identifies the dimensions which pertain purely to the security side. It develops a scale to measure those “security dimensions”. It shows that unique dimen...