Wouter Teepe

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On March 7, 2008 researchers and students of the Digital Security group of the Radboud University Nijmegen have discovered a serious security flaw in a widely used type of contactless smartcard [9], also called RFID tag. It concerns the ”Mifare Classic” RFID card produced by NXP (formerly Philips Semiconductors). Earlier, German researchers Karsten Nohl en(More)
Wouter Teepe a, Reind van de Riet b and Martin Olivier c a Department of Artificial Intelligence, State University of Groningen, Groningen, The Netherlands E-mail: wouter@teepe.com b Department of Mathematics and Computer Science, Vrije Universiteit, Amsterdam, The Netherlands E-mail: vdriet@cs.vu.nl c Department of Mathematics and Computer Science, Rand(More)
This paper introduces and describes new protocols for proving knowledge of secrets without giving them away: if the verifier does not know the secret, he does not learn it. This can all be done while only using one-way hash functions. If also the use of encryption is allowed, these goals can be reached in a more efficient way. We extend and use the GNY(More)
What would you do if you would be instructed to make a secure application built on the Mifare Classic? Arguably, due to the vulnerabilities shown in [5] and hinted at on [6], this is rather difficult and it may be easier to use to another chip. This document explores what the best is you can get, if the only option is Mifare Classic. We propose(More)
Nowadays in the information society, a lot of information available from different sources is combined to deduce new information. This everyday practice reduces the amount of privacy and anonymity that individuals have. At the same time, the combining of information does not always seamlessly succeed, for example local changes at an information source may(More)
We show that BAN logic, an epistemic logic for analyzing security protocols, contains an inference rule that wrongly ascribes a certain property to cryptographic hash functions. This faulty inference rule makes the BAN logic not ‘sound’. That is, it is possible to derive counterintuitive beliefs which cannot be computationally justified. We will prove this(More)
BAN logic, an epistemic logic for analyzing security protocols, contains an unjustifiable inference rule. The inference rule assumes that possession of H(X) (i.e., the cryptographic hash value of X) counts as a proof of possession of X, which is not the case. As a result, BAN logic exhibits a problematic property, which is similar to unsoundness, but not(More)
In-vitro experiments had been undertaken in order to clarify sperm selection by cervical mucus. Sperm samples, preferably with a high rate of abnormal cells, were obtained from fertile and infertile men for 35 penetration tests. Cervical mucus was collected from fertile women during praeovulatory phase. The penetration tests resulted in a statistically high(More)