Chris J. Mitchell

Bio: Chris J. Mitchell is an academic researcher from Royal Holloway, University of London. The author has contributed to research in topics: Authentication & Cryptography. The author has an hindex of 48, co-authored 397 publications receiving 10982 citations. Previous affiliations of Chris J. Mitchell include Johns Hopkins University & University of Portland.

Your Code Is My Code: Exploiting a Common Weakness in OAuth 2.0 Implementations

Abstract: Many millions of users routinely use their Google, Facebook and Microsoft accounts to log in to websites supporting OAuth 2.0-based single sign on. The security of OAuth 2.0 is therefore of critical importance, and it has been widely examined both in theory and in practice. In this paper we disclose a new class of practical attacks on OAuth 2.0 implementations, which we call Partial Redirection URI Manipulation Attacks. An attack of this type can be used by an attacker to gain a victim user’s OAuth 2.0 code (a token representing a right to access user data) without the user’s knowledge; this code can then be used to impersonate the user to the relevant relying party website. We examined 27 leading OAuth 2.0 identity providers, and found that 19 of them are vulnerable to these attacks.

Selective effects of errorful generation on recognition memory: the role of motivation and surprise

Abstract: The current research examined the effects of errorful generation on memory, focusing particularly on the roles of motivation and surprise. In two experiments, participants were first presen...

Using EMV Cards for Single Sign-On

Abstract: At present, network users have to manage a set of authentication credentials (usually a username/password pair) for every service with which they are registered. Single Sign-On (SSO) has been proposed as a solution to the usability, security and management implications of this situation. Under SSO, users authenticate themselves only once to an entity termed the ‘Authentication Service Provider’ (ASP) and are subsequently logged into disparate network Service Providers (SPs) without necessarily having to re-authenticate. The information about the user’s authentication status is handled between the ASP and the desired SP in a manner transparent to the user. In this paper we propose an SSO scheme where user authentication is based on payment cards conforming to the EMV industry standard. The card itself, in conjunction with the EMV architecture, takes the role of the ASP. The associated SSO protocol does not require online card issuer participation, preserves user mobility and does not put user’s financial data at risk.

Generating certification authority authenticated public keys in ad hoc networks

Abstract: In an ad hoc network, nodes may face the need to generate new public keys. To be verifiably authentic, these newly generated public keys need to be certified. However, because of the absence of a permanent communication infrastructure, a certification authority (CA) that can issue certificates may not always be reachable. The downside is that secure communication channels cannot be established. Previously proposed solutions do not guarantee that identities contained in certificates are valid or, when they do, they rely on neighbors to validate user-key bindings. However, there is no guarantee that nodes that are known in advance will always be present in the network. Therefore, neighbors are not always able to verify a node's identity before certificate issuance. In this paper we define a scheme that permits nodes to generate, on-demand, and independently of any third entity, public keys that can be authenticated with the aid of a unique certificate, issued by a CA at initialization. This certificate binds a valid identity to a hash code. We then extend this scheme to a solution permitting certificates to be generated, on-demand, and independently of any third entity, that can be authenticated with a unique signature generated by a CA. Finally we solve the problem of updated revocation information. Copyright © 2010 John Wiley & Sons, Ltd.

Applications of combinatorial mathematics

Abstract: The Combinatorics of some Abstract Data Types Recent Results in the Theory or Program Flowgraphs Applications of Combinatorics to Security The Regular Coloration of Graphs The Use of Combinatorial Structures in Communication Signal Design A Constructive Algorithm for Neural Network Design with Application to Channel Equalization The Weight Distribution of K M Codes Densities of Perfect Linear Complexity Profile Binary Sequences When Constraints are Easy to Satisfy A Unified Approach to Problems in Radio Channel Assignment Interconnection Networks Based on Two-dimensional de Bruijn Graphs A Graph Theoretic Solution to the Interface Equation Uniformly Optimally Reliable Networks for Vertex Failures Multi-Function Coding and Modulation for Spread Spectrum and CDMA with Inherent Security Multi-Stage Scheduling Problems with Precedence Constraints Frequency Assignment for Cellular Radio Networks

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Handbook of Applied Cryptography

Abstract: From the Publisher: A valuable reference for the novice as well as for the expert who needs a wider scope of coverage within the area of cryptography, this book provides easy and rapid access of information and includes more than 200 algorithms and protocols; more than 200 tables and figures; more than 1,000 numbered definitions, facts, examples, notes, and remarks; and over 1,250 significant references, including brief comments on each paper.

Tissue-based map of the human proteome

Abstract: Resolving the molecular details of proteome variation in the different tissues and organs of the human body will greatly increase our knowledge of human biology and disease. Here, we present a map of the human tissue proteome based on an integrated omics approach that involves quantitative transcriptomics at the tissue and organ level, combined with tissue microarray-based immunohistochemistry, to achieve spatial localization of proteins down to the single-cell level. Our tissue-based analysis detected more than 90% of the putative protein-coding genes. We used this approach to explore the human secretome, the membrane proteome, the druggable proteome, the cancer proteome, and the metabolic functions in 32 different tissues and organs. All the data are integrated in an interactive Web-based database that allows exploration of individual proteins, as well as navigation of global expression patterns, in all major tissues and organs in the human body.

Differential Power Analysis

Abstract: Cryptosystem designers frequently assume that secrets will be manipulated in closed, reliable computing environments. Unfortunately, actual computers and microchips leak information about the operations they process. This paper examines specific methods for analyzing power consumption measurements to find secret keys from tamper resistant devices. We also discuss approaches for building cryptosystems that can operate securely in existing hardware that leaks information.