Gridchain: an investigation of privacy for the future local distribution grid

As part of building the smart grid, there is a massive deployment of so-called smart meters that aggregate information and communicate with the back-end office, apart from measuring properties of the local network. Detailed measurements and communication of, e.g., consumption allows for remote billing, but also in finding problems in the distribution of power and overall to provide data to be used to plan future upgrades of the network. From a security perspective, a massive deployment of such Internet of Things (IoT) components increases the risk that some may be compromised or that collected data are used for privacy-sensitive inference of the consumption of households. In this paper, we investigate the privacy concerns regarding detailed readings of smart meters for billing purposes. We present Gridchain, a solution where households can opt-in to hide their consumption patterns and thus make Non-Intrusive Load Monitoring (NILM) more challenging. Households form groups where they can trade real consumption among themselves to achieve reported consumption that would be resistant to NILM. Gridchain is built on a publish/subscribe model and uses a permissioned blockchain to record any trades, meaning that dishonest households can be discovered and punished if they steal from other households in the group or the electricity company in the end. We implement and release a proof of concept of Gridchain and use public datasets to allow reproducibility. Our results show that even if an attacker has access to the reported electricity consumption of any member of a Gridchain group, this reported consumption is significantly far from the actual consumption to allow for a detailed fingerprint of the household activities

Modelling Cryptographic Distinguishers Using Machine Learning

Cryptanalysis is the development and study of attacks against cryptographic primitives and protocols. Many cryptographic properties rely on the difficulty of generating an adversary who, given an object sampled from one of two classes, correctly distinguishes the class used to generate that object. In the case of cipher suite distinguishing problem, the classes are two different cryptographic primitives. In this paper, we propose a methodology based on machine learning to automatically generate classifiers that can be used by an adversary to solve any distinguishing problem. We discuss the assumptions, a basic approach for improving the advantage of the adversary as well as a phenomenon that we call the “blind spot paradox”. We apply our methodology to generate distinguishers for the NIST (DRBG) cipher suite problem. Finally, we provide empirical evidence that the distinguishers might statistically have some advantage to distinguish between the DRBG used

The Medicine degree. A vision from students

El Grado en Medicina es uno de los grados más demandados por parte de los alumnos, como así lo demuestra su elevada nota de corte. Esto hace que los aspirantes se vean sometidos a una gran presión. Por eso y por la necesidad de evaluar habilidades sociales y emocionales indispensables para la práctica médica, nos planteamos si el método actual es el mejor y si la introducción de una prueba específica para Medicina ayudaría a definir mejor el perfil de estudiantes, más allá de la excelencia académica. La visión de los alumnos sobre el Grado en Medicina es, en general, muy positiva, sin olvidar que existen muchos aspectos que mejorar, especialmente en metodologías que aseguren una mayor motivación por parte del estudiantado y una mayor adherencia a los estudios. Por ello, desde el Consejo Estatal de Estudiantes de Medicina (CEEM) abogamos por la introducción de estrategias educativas alternativas que nos aparten del mero estudio pasivo, como son el aprendizaje basado en problemas, el aumento de peso en los planes de estudio de las prácticas clínicas, así como darle mayor importancia a aspectos no científicos del ámbito profesional como la bioética o las habilidades comunicativas. Además, consideramos esencial la evaluación de esta clase de competencias mediante la introducción de ECOE (evaluación clínica objetiva estructurada), debido a que es un método más fiable a la hora de evaluar competencias no teóricas

Hardening the security analysis of browser extensions

Browser extensions boost the browsing experience by a range of features from automatic translation and grammar correction to password management, ad blocking, and remote desktops. Yet the power of extensions poses significant privacy and security challenges because extensions can be malicious and/or vulnerable. We observe that there are gaps in the previous work on analyzing the security of browser extensions and present a systematic study of attack entry points in the browser extension ecosystem. Our study reveals novel password stealing, traffic stealing, and inter-extension attacks. Based on a combination of static and dynamic analysis we show how to discover extension attacks, both known and novel ones, and study their prevalence in the wild. We show that 1,349 extensions are vulnerable to inter-extension attacks leading to XSS. Our empirical study uncovers a remarkable cluster of "New Tab"extensions where 4,410 extensions perform traffic stealing attacks. We suggest several avenues for the countermeasures against the uncovered attacks, ranging from refining the permission model to mitigating the attacks by declarations in manifest files

After you, please: browser extensions order attacks and countermeasures

Browser extensions are small applications executed in the browser context that provide additional capabilities and enrich the user experience while surfing the web. The acceptance of extensions in current browsers is unquestionable. For instance, Chrome\u27s official extension repository has more than 63,000 extensions, with some of them having more than 10M users. When installed, extensions are pushed into an internal queue within the browser. The order in which each extension executes depends on a number of factors, including their relative installation times. In this paper, we demonstrate how this order can be exploited by an unprivileged malicious extension (i.e., one with no more permissions than those already assigned when accessing web content) to get access to any private information that other extensions have previously introduced. We propose a solution that does not require modifying the core browser engine, since it is implemented as another browser extension. We prove that our approach effectively protects the user against usual attackers (i.e., any other installed extension) as well as against strong attackers having access to the effects of all installed extensions (i.e., knowing who did what). We also prove soundness and robustness of our approach under reasonable assumptions

Security protocols for mobile ubiquitous e-health systems

Mención Internacional en el título de doctorWearable and implantable medical devices constitute an already established industry nowadays. According to a recent research [113], North America is currently the most important market followed by Europe, Asia-Pacific and the rest of the world. Additionally, the same document remarks the importance of the Asia-Pacific region due to the rising ageing population and the overpopulation in that area. The most common implantable medical devices include pacemakers, defibrillators, cochlear implants, insulin pumps, and neurostimulators among others. In recent years, the proliferation of smartphones and other mobile “smart” devices with substantial computational and communication capabilities have reshaped the way wireless body area network may be implemented. In their current generation (or in a near future), all of them share a common feature: wireless communication capabilities [127]. Moreover, implantable medical devices have the ability to support and store telemetry data facilitating the remote monitoring of the patient. Medical devices can be part of a wireless body area network, operating both as sensors and as actuators and making decisions in real time. On the other hand, a new kind of devices called wearables such as smart bracelets or smart watches have been equipped with several sensors like Photoplethysmogram (PPG) to record the heart beats, accelerometers to count the steps or Global Positioning System (GPS) to geopositioning users and were originally conceived as cheap solutions to help people to improve their workout. However these devices have demonstrated to be quite useful in many healthcare environments due to a huge variety of different and low-cost medical sensors. Thus, patients can be monitored for long periods of time without interfering in their daily life and taking their vital signs constantly under control. Security and privacy issues have been described as two of the most challenging problems of implantable medical devices and, more generally, wireless body area networks [6, 47, 84, 103]. As an example, it has been demonstrated that somebody equipped with a low cost device can eavesdrop on the data exchanged between a reader and a peacemaker and may even induce a cardiac arrest [71]. Health-related data have been the focus of several attacks almost since the adoption of computers in the healthcare domain. As a recent example, in 2010 personal data from more than 26 million of veterans were stolen from the Department of Veterans Affairs’ database in the US by an employee who had access to the database [104]. The Ponemon Institute pointed out that Germany and the US spent in 2013 more than $7.56 and$11 millions, respectively, to protect personal health records from attacks. This PhD dissertation explores the security and privacy of data in healthcare environments where confidential information is measured in real time by some sensors placed in, on, or around the human body. Security and privacy in medical conditions have been widely studied by the research community, nonetheless with the recent boom of wearable devices, new security issues have arisen. The first part of this dissertation is dedicated to the introduction and to expose both the main motivation and objectives of this PhD Thesis. Additionally the contributions and the organization of this document are also presented. In the second part a recent proposal has been analysed from the security and privacy points of view. From this study, vulnerabilities concerning to full disclosure, impersonation, traceability, de-synchronization, and Denial-of-Service (DoS) attacks have been found. These attacks make the protocol infeasible to be introduced with an adequate security and sufficient privacy protection level. Finally, a new protocol named Fingerprint⁺ protocol for Internet of Thing (IoT) is presented, which is based on ISO/IEC 9798-2 and ISO/IEC 18000-6C and whose security is formally verified using BAN logic. In the third part of this dissertation, a new system based on International Standard Organization (ISO) standards and security National Institute of Standards and Technology (NIST) recommendations have been proposed. First, we present a mutual entity authentication protocol inspired on ISO/IEC 9798 Part 2. This system could be deployed in a hospital where Radio Frequency IDentification (RFID) technology may be used to prune blood-handling errors, i.e., the identities of the patients and blood bags are confirmed (authentication protocol) and after that the matching between both entities is checked (verification step). Second, a secure messaging protocol inspired on ISO/IEC 11770 Part 2 and similar to that used in electronic passports is presented. Nowadays the new generation of medical implants possess wireless connectivity. Imagine a doctor equipped with a reader aims to access the records of vital signals stored on the memory of an implant. In this scenario, the doctor (reader) and the patient (implant) are first mutually authenticated and then a secure exchange of data can be performed. The fourth part of this Thesis provides an architecture based on two cryptographic protocols, the first one is for publishing personal data in a body area network composed of different sensors whereas the second one is designed for sending commands to those sensors by guaranteeing the confidentiality and fine-grained access control to the private data. Both protocols are based on a recently proposed public cryptography paradigm named ciphertext policy attribute-based encryption scheme which is lightweight enough to be embedded into wearable devices and sensors. Contrarily to other proposals made on this field, this architecture allows sensors not only to encrypt data but also to decrypt messages generated by other devices. The fifth part presents a new decentralized attribute based encryption scheme named Decentralized Ciphertext-Policy Attribute Based Searchable Encryption that incorporates ciphertext-policy attribute-based encryption with keyword search over encrypted data. This scheme allows users to (a) encrypt their personal data collected by a Wireless Body Area Network (WBAN) according to a policy of attributes; (b) define a set of keywords to enable other users (e.g., hospital stuff) to perform encrypted search over their personal (encrypted) data; (c) securely store the encrypted data on a semi-honest server and let the semi-honest server run the (encrypted) keyword search. Note that any user can perform a keyword query on the encrypted data, however the decryption of the resulting ciphertexts is possible only for users whose attribute satisfy the policy with which the data had been encrypted. We state and prove the security of our scheme against an honest-but-curious server and a passive adversary. Finally, we implement our system on heterogeneous devices and demonstrate its efficiency and scalability. Finally, this document ends with a conclusions achieved during this PhD and a summary of the main published contributions.Los dispositivos médicos implantables como los marcapasos o las bombas de insulina fueron concebidas originalmente para controlar automáticamente ciertos parámetros biológicos y, llegado el caso, poder actuar ante comportamientos anómalos como ataques cardíacos o episodios de hipoglucemia. Recientemente, han surgido uno dispositivos llamados wearables como las pulseras cuantificadoras, los relojes inteligentes o las bandas pectorales. Estos dispositivos han sido equipados con un número de sensores con capacidad de monitorizar señales vitales como el ritmo cardíaco, los movimientos (acelerómetros) o sistemas de posicionamiento (GPS) entre otros muchas opciones, siendo además una solución asequible y accesible para todo el mundo. A pesar de que el propósito original fue la mejora del rendimiento en actividades deportivas, estos dispositivos han resultado ser de gran utilidad en entornos médicos debido a su amplia variedad de sensores. Esta tecnología puede ayudar al personal médico a realizar seguimientos personalizados, constantes y en tiempo real del comportamiento de los pacientes, sin necesidad de interferir en sus vidas cotidianas. Esta Tesis doctoral está centrada en la seguridad y privacidad en entornos médicos, donde la información es recogida en tiempo real a través de una serie de sensores que pueden estar implantados o equipados en el propio paciente. La seguridad y la privacidad en entornos médicos ha sido el foco de muchos investigadores, no obstante con el reciente auge de los wearables se han generado nuevos retos debido a que son dispositivos con fuertes restricciones de cómputo, de memoria, de tamaño o de autonomía. En la primera parte de este documento, se introduce el problema de la seguridad y la privacidad en el paradigma de Internet de las cosas y haciendo especial hincapié en los entornos médicos. La motivación así como los principales objetivos y contribuciones también forman parte de este primer capítulo introductorio. La segunda parte de esta Tesis presenta un nuevo protocolo de autenticación basado en RFID para IoT. Este capítulo analiza previamente, desde el punto de vista de la seguridad y la privacidad un protocolo publicado recientemente y, tras demostrar que carece de las medidas de seguridad suficientes, un nuevo protocolo llamado Fingerprint⁺ compatible con los estándares de seguridad definidos en el estándar ISO/IEC 9798-2 y EPC-C1G2 (equivalente al estándard ISO/IEC 18000-6C) ha sido propuesto. Un nuevo sistema basado en estándares ISO y en recomendaciones realizadas por el NIST ha sido propuesto en la tercera parte de esta Tesis. En este capítulo se presentan dos protocolos bien diferenciados, el primero de ellos consiste en un protocolo de autenticación basado en el estándar ISO/IEC 9798 Part 2. A modo de ejemplo, este protocolo puede evitar problemas de compatibilidad sanguínea, es decir, primero se confirma que el paciente es quien dice ser y que la bolsa de sangre realmente contiene sangre (proceso de autenticación). Posteriormente se comprueba que esa bolsa de sangre va a ser compatible con el paciente (proceso de verificación). El segundo de los protocolos propuestos consiste en un protocolo seguro para el intercambio de información basado en el estándar ISO/IEC 11770 Part 2 (el mismo que los pasaportes electrónicos). Siguiendo con el ejemplo médico, imaginemos que un doctor equipado con un lector de radiofrecuencia desea acceder a los datos que un dispositivo implantado en el paciente está recopilando. En este escenario tanto el lector como el implante, se deben autenticar mutuamente para poder realizar el intercambio de información de manera segura. En el cuarto capítulo, una nueva arquitectura basada en el modelo de Publish/Subscribe ha sido propuesto. Esta solución está compuesta de dos protocolos, uno para el intercambio de información en una red de área personal y otro para poder reconfigurar el comportamiento de los sensores. Ambos protocolos están diseñados para garantizar tanto la seguridad como la privacidad de todos los datos que se envían en la red. Para ello, el sistema está basado en un sistema de criptografía de clave pública llamado Attribute Based Encryption que es suficientemente ligero y versátil como para ser implementado en dispositivos con altas restricciones de cómputo y de memoria. A continuación, en el quinto capítulo se propone una solución completamente orientada a entornos médicos donde la información que los sensores obtienen de los pacientes es cifrada y almacenada en servidores públicos. Una vez en estos servidores, cualquier usuario con privilegios suficientes puede realizar búsquedas sobre datos cifrados, obtener la información y descifrarla. De manera adicional, antes de que los datos cifrados se manden a la nube, el paciente puede definir una serie de palabras claves que se enlazarán a los datos para permitir posteriormente búsquedas y así obtener la información relacionada a un tema en concreto de manera fácil y eficiente. El último capítulo de esta Tesis se muestran las principales conclusiones obtenidas así como un resumen de las contribuciones científicas publicadas durante el período doctoral.Programa Oficial de Doctorado en Ciencia y Tecnología InformáticaPresidente: Arturo Ribagorda Garnacho.- Secretario: Jorge Blasco Alís.- Vocal: Jesús Garicia López de Lacall

waveSLAM: Empowering accurate indoor mapping using off-the-shelf millimeter-wave self-sensing

Proceedings of: 2023 IEEE 98th Vehicular Technology Conference: VTC2023-Fall, 10-13 October 2023, Hong Kong.This paper presents the design, implementation and evaluation of waveSLAM, a low-cost mobile robot system that uses the millimetre wave (mmWave) communication devices to enhance the indoor mapping process targeting environments with reduced visibility or glass/mirror walls. A unique feature of waveSLAM is that it only leverages existing Commercial-Off-The-Shelf (COTS) hardware (Lidar and mmWave radios) that are mounted on mobile robots to improve the accurate indoor mapping achieved with optical sensors. The key intuition behind the waveSLAM design is that while the mobile robots moves freely, the mmWave radios can periodically exchange angle and distance estimates between themselves (self-sensing) by bouncing the signal from the environment, thus enabling accurate estimates of the target object/material surface. Our experiments verify that waveSLAM can archive cm-level accuracy with errors below 22 cm and 20◦ in angle orientation which is compatible with Lidar when building indoor maps.This work has been partially funded by the European Union's Horizon Europe research and innovation program under grant agreement No 101095759 (Hexa-X-II) and the Spanish Ministry of Economic Affairs and Digital Transformation and the European Union-Next Generation EU through the UNICO 5G I+D 6G-EDGEDT

Are chrome extensions compliant with the spirit of least privilege?

Extensions are small applications installed by users and enrich the user experience of browsing the Internet. Browsers expose a set of restricted APIs to extensions. To be used, extensions need to list the permissions associated with these APIs in a mandatory extension file named manifest. In particular, Chrome’s permission ecosystem was designed in the spirit of the least privilege. Yet, this paper demonstrates that 39.8% of the analyzed extensions provided by the official Web Store are compliant with the spirit of least privilege. Also, we develop: (1) a browser extension to make aware regular users of the permissions the extensions they install; (2) a web app where extensions developers can check whether their extensions are compliant with the spirit of the least privileged; and (3) a set of scripts that can be part of the vendors’ acceptance criteria such that when developers upload their extensions to the official repositories, the scripts automatically analyze the extensions and generate a report about the permissions and the usage

Application of Quantum Computing to Accurate Positioning in 6G Indoor Scenarios

[EN] 6G will lay its foundations on new paradigms and requirements. This new technology is expected to provide global coverage, exploring a huge spectral chunk (sub-6 GHz, mmWave, THz and optical frequency bands) to further increase data rates and connection density. In addition, 6G networks will enable a new range of smart applications with the aid of Artificial Intelligence, Big Data technologies and the emerging paradigms of Quantum Computing and Quantum Machine Learning. This paper focuses on these new paradigms and proposes an indoor location method based on the well known Euclidean Distance in its quantum version. Specifically, an example of this use case is shown, which is executed in one quantum computer from IBM Quantum Experience. The paper analyses the obtained results while exploring new challenges and fields of application of the technology. Results show that the quantum approach is accurate enough to calculate Euclidean Distance between two vectors while outperforming classical computation if the vector size is big enough.Urgelles-Pérez, H.; Picazo-Martínez, P.; Monserrat Del Río, JF. (2022). Application of Quantum Computing to Accurate Positioning in 6G Indoor Scenarios. IEEE. 1-5. https://doi.org/10.1109/ICC45855.2022.98385231