In a recent paper (AMIS, 6(2S), 2012), Lee proposed a dynamic ID-based user authentication scheme based on smart card which is believed to have many abilities to resist a range of network attacks. In this paper, we analyze the security of Lee’s scheme and show that the scheme is in fact insecure against insider-assisted attack, even if the adversary doesn’t know the secret information stored in...

The objective of steganography is to conceal the presence of a secret communication. Nevertheless, with the development of steganalytic attack, also known as steganalysis, there are many statistical methods to estimate the presence and ratio of secret messages. The chi square (χ 2 ) attack and regular-singular (RS) attack are two well recognized and widely applied statistical steganalysis schem...

Group Key Transfer (GKT) protocols allow multiple parties to share a common secret key: a trusted Key Generation Center (KGC) selects a uniformly random value that has never been used before and securely distributes it to the legitimate principals. The paper restricts to GKT based on secret sharing; it briefly reviews the security goals and the existing formal security models. We motivate our w...

Recently, some group key transfer protocols are proposed using Shamir’s secret sharing, which are claimed to be secure to resist the insider attack and the outsider attack. In fact, some claims are not really true. In this paper, we review the recently proposed protocol by Yuan et al. and the cryptanalysis presented by Olimid, then give the improved version to guarantee the security and low com...

In this paper, we fully break the Algebraic Surface Cryptosystem (ASC for short) proposed at PKC’2009 [3]. This system is based on an unusual problem in multivariate cryptography: the Section Finding Problem. Given an algebraic surface X(x,y, t) ∈ Fp[x,y, t] such that degxy X(x,y, t) = w, the question is to find a pair of polynomials of degree d, ux(t) and uy(t), such that X(ux(t),uy(t), t) = 0...

With the nearly instantaneous spread of information in modern society, policies regarding the disclosure of information about security vulnerabilities have become the focus of significant discussion. The fundamental debate centers on tradeoffs inherent in disclosing information that security professionals need, but that can also be used for nefarious purposes. Our empirical study compares attac...

Radio Frequency Identification (RFID) applications have spread all over the world. In order to provide their security and privacy, researchers proposed different kinds of protocols. In this paper, we analyze the privacy of a new protocol, proposed by Yu-Jehn in 2015 which is based on Electronic Product Code Class1 Generation 2 (EPC C1 G2) standard. By applying the Ouafi_Phan privacy model, we s...

Security ICs are vulnerable to side-channel attacks (SCAs) that find the secret key by monitoring the power consumption and other information that is leaked by the switching behavior of digital CMOS gates. This paper describes a side-channel attack resistant coprocessor IC and its design techniques. The IC has been fabricated in 0.18μm CMOS. The coprocessor, which is used for embedded cryptogra...

In this paper we present a practically feasible attack on RSA-based sessions in SSL/TLS protocols. These protocols incorporate the PKCS#1 (v. 1.5) encoding method for the RSA encryption of a premaster-secret value. The premaster-secret is the only secret value that is used for deriving all the particular session keys. Therefore, an attacker who can recover the premastersecret can decrypt the wh...

Many network devices, such as routers, firewalls, and intrusion detection systems, usually maintain perconnection state in a hash table. However, hash tables are susceptible to algorithmic complexity attacks, in which the attacker degenerates the hash into a simple linked list. A common counter-measure is to randomize the hash table by adding a secret value, known only to the device, as a param...