In this work, we consider privacy in Radio Frequency IDentification (RFID) systems. Our contribution is threefold: (1) We propose a simple, formal definition of strong privacy useful for basic analysis of RFID systems, as well as a di#erent (weaker) definition applicable to multi-verifier systems; (2) We apply our definition to reveal vulnerabilities in several proposed privacy-enhancing RFID protocols; and (3) We formally analyze and suggest improvements to "Hash-Locks," one of the first privacy-enhancing RFID protocols in the literature.

We present the design and evaluation of an 802.11-like wireless link layer protocol that obfuscates all transmitted bits to increase privacy. This includes explicit identifiers such as MAC addresses, the contents of management messages, and other protocol fields that the existing 802.11 protocol relies on to be sent in the clear. By obscuring these fields, we greatly increase the difficulty of identifying or profiling users from their transmissions in ways that are otherwise straightforward. Our design, called SlyFi, is nearly as efficient as existing schemes such as WPA for discovery, link setup, and data delivery despite its heightened protections; transmission requires only symmetric key encryption and reception requires a table lookup followed by symmetric key decryption. Experiments using our implementation on Atheros 802.11 drivers show that SlyFi can discover and associate with networks faster than 802.11 using WPA-PSK. The overhead SlyFi introduces in packet delivery is only slightly higher than that added by WPA-CCMP encryption (10 % vs. 3 % decrease in throughput).

The number of RFID devices used in everyday life has increased, along with concerns about their security and user privacy. This paper describes our initial findings on practical attacks that we implemented against ‘proximity ’ (ISO 14443 A) type RFID tokens. Focusing mainly on the RF communication interface we discuss the results and implementation of eavesdropping, unauthorized scanning and relay attacks. Although most of these attack scenarios are regularly mentioned in literature little technical details have been published previously. We also present a short overview of mechanisms currently available to prevent these attacks 1. 1.

Abstract. RFID-enabled credit cards are widely deployed in the United States and other countries, but no public study has thoroughly analyzed the mechanisms that provide both security and privacy. Using samples from a variety of RFID-enabled credit cards, our study observes that (1) the cardholder’s name and often credit card number and expiration are leaked in plaintext to unauthenticated readers, (2) our homemade device costing around $150 effectively clones one type of skimmed cards — providing a proof-of-concept of the RF replay attack for cards, (3) information revealed by the RFID transmission cross contaminates the security of non-RFID payment media, and (4) RFID-enabled credit cards are susceptible in various degrees to a range of other traditional RFID attacks such as skimming and relaying.

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We analyze three new consumer electronic gadgets in order to gauge the privacy and security trends in massmarket UbiComp devices. Our study of the Slingbox Pro uncovers a new information leakage vector for encrypted streaming multimedia. By exploiting properties of variable bitrate encoding schemes, we show that a passive adversary can determine with high probability the movie that a user is watching via her Slingbox, even when the Slingbox uses encryption. We experimentally evaluated our method against a database of over 100 hours of network traces for 26 distinct movies. Despite an opportunity to provide significantly more location privacy than existing devices, like RFIDs, we find that an attacker can trivially exploit the Nike+iPod Sport Kit’s design to track users; we demonstrate this with a GoogleMaps-based distributed surveillance system. We also uncover security issues with the way Microsoft Zunes manage their social relationships. We show how these products’ designers could have significantly raised the bar against some of our attacks. We also use some of our attacks to motivate fundamental security and privacy challenges for future UbiComp devices.

Abstract. In this paper, we analyze the security vulnerabilities of two ultra-lightweight RFID mutual authentication protocols: LMAP and M 2 AP, which are recently proposed by Peris-Lopez et al. We identify two effective attacks, namely De-synchronization attack and Full-disclosure attack, against their protocols. The former attack can break the synchronization between the RFID reader and the tag in a single protocol run so that they can not authenticate each other in any following protocol runs. The latter attack can disclose all the secret information stored on a tag by interrogating the tag multiple times. Thus it compromises the tag completely. Moreover, we point out the potential countermeasures to improve the security of above protocols. 1

RFID technology arouses great interests from both its advocates and opponents because of the promising but privacy-threatening nature of low-cost RFID tags. A main privacy concern in RFID systems results from clandestine scanning through which an adversary could conduct silent tracking and inventorying of persons carrying tagged objects. Thus, the most important security requirement in designing RFID protocols is to ensure untraceability of RFID tags by unauthorized parties (even with knowledge of a tag secret due to no physical security of low-cost RFID tags). Previous work in this direction mainly focuses on backward untraceability, requiring that compromise of a tag secret should not help identify the tag from past communication transcripts. However, in this paper, we argue that forward untraceability, i.e., untraceability of future events even with knowledge of a current tag secret, should be considered as an equally or even more important security property in RFID protocol designs. Furthermore, RFID tags may often change hands during their lifetime and thus the problem of tag ownership transfer should be dealt with as another key issue in RFID privacy problems; once ownership of a tag is transferred to another party, the old owner should not be able to read the tag any more. It is rather obvious that complete transfer of tag ownership is possible only if some degree of forward untraceability is provided. We propose a strong and robust RFID authentication protocol satisfying both forward and backward untraceability and enabling complete transfer of tag ownership. 1

A client can use a content distribution network to securely download software updates. These updates help to patch everyday bugs, plug security vulnerabilities, and secure critical infrastructure. Yet challenges remain for secure content distribution: many deployed software update mechanisms are insecure, and emerging technologies pose further hurdles for deployment. Our analysis of several popular software update mechanisms shows that deployed systems often rely on trusted networks to distribute critical software updates — despite the research progress in secure content distribution. We demonstrate how many deployed systems are susceptible to weak man-in-the-middle attacks. Furthermore, emerging technologies such as mobile devices, sensors, medical devices, and RFID tags present new challenges for secure software updates. Sporadic network connectivity and limited power, computation, and storage require a rethinking of traditional approaches for secure content distribution on embedded devices. 1

Abstract. Authentication has an important role in many RFID applications for providing security and privacy. In this paper we focus on investigating how RFID can be used in product authentication in supply chain applications and a review of existing approaches is provided. The different categories of RFID product authentication approaches are analyzed within the context of anticounterfeiting and fields where future research is needed are identified. 1