Publications related to Security token

Revisiting Character-level Adversarial Attacks for Language Models

Volkan Cevher, Grigorios Chrysos, Fanghui Liu, Yongtao Wu, Elias Abad Rocamora

Adversarial attacks in Natural Language Processing apply perturbations in the character or token levels. Token-level attacks, gaining prominence for their use of gradient-based methods, are susceptible to altering sentence semantics, leading to invalid adv ...

2024

Anonymous Tokens with Stronger Metadata Bit Hiding from Algebraic MACs

Serge Vaudenay, Fatma Betül Durak

On the one hand, the web needs to be secured from malicious activities such as bots or DoS attacks; on the other hand, such needs ideally should not justify services tracking people's activities on the web. Anonymous tokens provide a nice tradeoff between ...

2023

VETIM: Expanding the Vocabulary of Text-to-Image Models only with Text

Sabine Süsstrunk, Radhakrishna Achanta, Mahmut Sami Arpa, Martin Nicolas Everaert

Text-to-image models, such as Stable Diffusion, can generate high-quality images from simple textual prompts. With methods such as Textual Inversion, it is possible to expand the vocabulary of these models with additional concepts, by learning the vocabula ...

BMVA2023

BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy

Mathias Josef Payer, Daniele Antonioli

Bluetooth is a pervasive wireless technology specified in an open standard. The standard defines Bluetooth Classic (BT) for high-throughput wireless services and Bluetooth Low Energy (BLE) very low-power ones. The standard also specifies security mechanism ...

ASSOC COMPUTING MACHINERY2022

Security Measures for Grids Against Rank-1 Undetectable Time-Synchronization Attacks

Jean-Yves Le Boudec, Marguerite Marie Nathalie Delcourt

Time-synchronization attacks on phasor measurement units (PMUs) pose a real threat to smart grids; it was shown that they are feasible in practice and that they can have a nonnegligible negative impact on state estimation, without triggering the bad data d ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

BioLocker: A Practical Biometric Authentication Mechanism based on 3D Fingervein

Serge Vaudenay, Loïs Evan Huguenin-Dumittan, Fatma Betül Durak

We design a consecution of protocols which allows organizations to have secure strong access control of their users to their desktop machines based on biometry. It provides both strong secure authentication and privacy. Moreover, our mechanism allows the s ...

Springer, Cham2020

BIAS: Bluetooth Impersonation AttackS

Daniele Antonioli

Bluetooth (BR/EDR) is a pervasive technology for wireless communication used by billions of devices. The Bluetooth standard includes a legacy authentication procedure and a secure authentication procedure, allowing devices to authenticate to each other usi ...

IEEE COMPUTER SOC2020

Integrated, Eddy-Current-Based Sensing of Rotor Position for Magnetic Levitation

Yves Perriard, Sean Thomas, Juan Patricio Tomás Peralta Fierro

Magnetically-levitated drives are compelling in applications where long-lifetime operation or process chamber encapsulation is a requirement. To exploit these advantages, contactless position sensors are needed for position information of the rotor. Off-th ...

IEEE2020

Key Negotiation Downgrade Attacks on Bluetooth and Bluetooth Low Energy

Daniele Antonioli

Bluetooth (BR/EDR) and Bluetooth Low Energy (BLE) are pervasive wireless technologies specified in the Bluetooth standard. The standard includes key negotiation protocols used to generate long-term keys (during pairing) and session keys (during secure conn ...

ASSOC COMPUTING MACHINERY2020

Biometric Face Presentation Attack Detection with Multi-Channel Convolutional Neural Network

Sébastien Marcel, André Anjos, Zohreh Mostaani

Face recognition is a mainstream biometric authentication method. However, vulnerability to presentation attacks (a.k.a spoofing) limits its usability in unsupervised applications. Even though there are many methods available for tackling presentation atta ...

2020

Feasibility of Time Synchronization Attacks against PMU-based State-Estimation

Jean-Yves Le Boudec, Mario Paolone, Sergio Barreto Andrade, Marguerite Marie Nathalie Delcourt, Gyorgy Miklos Dan

The emerging measurement technology of phasor measurement units (PMUs) makes it possible to estimate the state of electrical grids in real-time, thus opening the way to new protection and control applications. PMUs rely on precise time synchronization, the ...

2019

Implications of Position in Cryptography

Handan Kilinç Alper

In our daily lives, people or devices frequently need to learn their location for many reasons as some services depend on the absolute location or the proximity. The outcomes of positioning systems can have critical effects e.g., on military, emergency. Th ...

EPFL2018

Contactless Access Control Based on Distance Bounding

Serge Vaudenay

Contactless access control systems are critical for security but often vulnerable to relay attacks. In this paper, we define an integrated security and privacy model for access control using distance bounding (DB) which is the most robust solution to preve ...

2017

Emerging Technology Based Design of Primitives for Hardware Security

Giovanni De Micheli, Pierre-Emmanuel Julien Marc Gaillardon

Hardware security concerns such as IP piracy and hardware Trojans have triggered research into circuit protection and malicious logic detection from various design perspectives. In this paper, emerging technologies are investigated by leveraging their uniq ...

Assoc Computing Machinery2016

Challenges in Distance Bounding

Serge Vaudenay

Smartcard-based protocols represent an increasingly large share of the wireless authentication market, from contactless payments to remote car unlocking. Unfortunately, relay attacks pose a significant threat to these wireless solutions. However, this risk ...

Ieee Computer Soc2015

TOA: a tag-owner-assisting RFID authentication protocol toward access control and ownership transfer

Chao Wang, Qiang Wang, Chen Zhang, Lei Xie

This paper addresses radio frequency identification (RFID) authentication and ownership transfer in offline scenarios. Four typical related works are reviewed in detail. A series of shortcomings and vulnerabilities of them are pointed out. A new RFID authe ...

Wiley-Blackwell2014

Bounded Tamper Resilience: How to go beyond the Algebraic Barrier

Sebastian Faust

Related key attacks (RKAs) are powerful cryptanalytic attacks where an adversary can change the secret key and observe the effect of such changes at the output. The state of the art in RKA security protects against an a-priori unbounded number of certain a ...

2013

The Inconvenient Truth about Web Certificates

Jean-Pierre Hubaux, Julien Freudiger, Nevena Vratonjic, Vincent Bindschaedler

HTTPS is the de facto standard for securing Internet communications. Although it is widely deployed, the security provided with HTTPS in practice is dubious. HTTPS may fail to provide security for multiple reasons, mostly due to certificate-based authentic ...

2011

A Fault-Tolerant Token-Based Atomic Broadcast Algorithm

André Schiper, Nils Richard Ekwall

Many atomic broadcast algorithms have been published in the last 20 years. Token-based algorithms represent a large class of these algorithms. Interestingly, all the token-based atomic broadcast algorithms rely on a group membership service and none of the ...

2011

Privacy of Recent RFID Authentication Protocols

Khaled Ouafi

Privacy is a major concern in RFID systems, especially with widespread deployment of wireless-enabled interconnected personal devices e.g. PDAs and mobile phones, credit cards, e-passports, even clothing and tires. An RFID authentication protocol should no ...

Springer2008