2020
Authors
Johnson, SA; Ferreira, JF; Mendes, A; Cordry, J;
Publication
AsiaCCS
Abstract
The choice of password composition policy to enforce on a password-protected system represents a critical security decision, and has been shown to significantly affect the vulnerability of user-chosen passwords to guessing attacks. In practice, however, this choice is not usually rigorous or justifiable, with a tendency for system administrators to choose password composition policies based on intuition alone. In this work, we propose a novel methodology that draws on password probability distributions constructed from large sets of real-world password data which have been filtered according to various password composition policies. Password probabilities are then redistributed to simulate different user password reselection behaviours in order to automatically determine the password composition policy that will induce the distribution of user-chosen passwords with the greatest uniformity, a metric which we show to be a useful proxy to measure overall resistance to password guessing attacks. Further, we show that by fitting power-law equations to the password probability distributions we generate, we can justify our choice of password composition policy without any direct access to user password data. Finally, we present Skeptic - -a software toolkit that implements this methodology, including a DSL to enable system administrators with no background in password security to compare and rank password composition policies without resorting to expensive and time-consuming user studies. Drawing on 205,176,321 passwords across 3 datasets, we lend validity to our approach by demonstrating that the results we obtain align closely with findings from a previous empirical study into password composition policy effectiveness.
2020
Authors
Lopes, N; Martins, R; Correia, ME; Serrano, S; Nunes, F;
Publication
PROCEEDINGS OF THE 2020 6TH INTERNATIONAL WORKSHOP ON CONTAINER TECHNOLOGIES AND CONTAINER CLOUDS (WOC '20)
Abstract
Nowadays the use of container technologies is ubiquitous and thus the need to make them secure arises. Container technologies such as Docker provide several options to better improve container security, one of those is the use of a Seccomp profile. A major problem with these profiles is that they are hard to maintain because of two different factors: they need to be updated quite often and present a complex and time consuming task to determine exactly what to update, therefore not many people use them. The research goal of this paper is to make Seccomp profiles a viable technique in a production environment by proposing a reliable method to generate custom Seccomp profiles for arbitrary containerized application. This research focused on developing a solution with few requirements allowing for an easy integration with any environment with no human intervention. Results show that using a custom Seccomp profile can mitigate several attacks and even some zero day vulnerabilities on containerized applications. This represents a big step forward on using Seccomp in a production environment, which would benefit users worldwide.
2020
Authors
Brito, T; Lima, J; Costa, P; Matellan, V; Braun, J;
Publication
FOURTH IBERIAN ROBOTICS CONFERENCE: ADVANCES IN ROBOTICS, ROBOT 2019, VOL 1
Abstract
The collaboration between humans and machines, where humans can share the same work environment without safety equipment due to the collision avoidance characteristic is one of the research topics for the Industry 4.0. This work proposes a system that acquires the space of the environment through an RGB-Depth sensor, verifies the free spaces in the created Point Cloud and executes the trajectory of the collaborative manipulator avoiding collisions. It is demonstrated a simulated environment before the system in real situations, in which the movements of pick-and-place tasks are defined, diverting from virtual obstacles with the RGB-Depth sensor. It is possible to apply this system in real situations with obstacles and humans, due to the results obtained in the simulation. The basic structure of the system is supported by the ROS software, in particular, the MoveIt! and Rviz. These tools serve both for simulations and for real applications. The obtained results allow to validate the system using the algorithms PRM and RRT, chosen for being commonly used in the field of robot path planning.
2020
Authors
Pereira, Ana I.; Fernandes, Florbela P.; Pacheco, Maria F.; Barros, Paula Maria; Cordeiro, Edite; Silva, Flora; Geraldes, Carla A.S.; Vaz, Clara B.; Barbedo, Inês; Barros, Elisa; Almeida, João P.; Martins, Cristina; Pires, Manuel Vara;
Publication
International Conference Future of Education
Abstract
MathE (mathe.pixel-online.org) is an e-learning platform for higher education developed and implemented by a consortium of seven institutional partners from five European countries. The aim of the project is to enhance the quality of teaching and improve pedagogies and assessment methods by facilitating the identification of students’ gaps in Math, providing appropriate digital tools and promoting self-evaluation with immediate feedback. The Polytechnic Institute of Bragança (IPB), in Portugal, is one of the consortium members: sixteen of its teachers collaborate in the development of this platform, being responsible for thirteen of the topics/subtopics in which the platform is structured. Such topics cover a wide range of contents, from linear transformations to integration, from graph theory to probabilities. The articulation of the topics of the MathE collection corresponds to the canonic mathematics content of engineering, business and education degrees. The MathE platform is organized into three main sections: Student´s Assessment, MathE Library and Community of Practice. So far, IPB has already developed a collection of around 800 questions for the student´s assessment section and is currently developing the MathE Library. More than 350 students from IPB are using the MathE platform; some offered as volunteers, whose role is testing the behavior of the platform as well as looking for bugs and other details that require improvement, while others are already using the platform in their study. The feedback received up until now is quite encouraging.
2020
Authors
Caratti o Garatti, A; Fedriani, R; Garcia Lopez, R; Koutoulaki, M; Perraut, K; Linz, H; Brandner, W; Garcia, P; Klarmann, L; Henning, T; Labadie, L; Sanchez-Bermudez, J; Lazareff, B; van Dishoeck, EF; Caselli, P; de Zeeuw, PT; Bik, A; Benisty, M; Dougados, C; Ray, TP; Amorim, A; Berger, J; Clénet, Y; Coudé du Foresto, V; Duvert, G; Eckart, A; Eisenhauer, F; Gao, F; Gendron, E; Genzel, R; Gillessen, S; Gordo, P; Jocou, L; Horrobin, M; Kervella, P; Lacour, S; Le Bouquin, J; Léna, P; Grellmann, R; Ott, T; Paumard, T; Perrin, G; Rousset, G; Scheithauer, S; Shangguan, J; Stadler, J; Straub, O; Straubmeier, C; Sturm, E; Thi, WF; Vincent, FH; Widmann, F;
Publication
ASTRONOMY & ASTROPHYSICS
Abstract
Context. The inner regions of the discs of high-mass young stellar objects (HMYSOs) are still poorly known due to the small angular scales and the high visual extinction involved.Aims. We deploy near-infrared spectro-interferometry to probe the inner gaseous disc in HMYSOs and investigate the origin and physical characteristics of the CO bandhead emission (2.3-2.4 mu m).Methods. We present the first GRAVITY/VLTI observations at high spectral (R=4000) and spatial (mas) resolution of the CO overtone transitions in NGC 2024 IRS 2.Results. The continuum emission is resolved in all baselines and is slightly asymmetric, displaying small closure phases (<= 8 degrees). Our best ellipsoid model provides a disc inclination of 34 degrees +/- 1 degrees, a disc major axis position angle (PA) of 166 degrees +/- 1 degrees, and a disc diameter of 3.99 +/- 0.09 mas (or 1.69 +/- 0.04 au, at a distance of 423 pc). The small closure phase signals in the continuum are modelled with a skewed rim, originating from a pure inclination effect. For the first time, our observations spatially and spectrally resolve the first four CO bandheads. Changes in visibility, as well as differential and closure phases across the bandheads are detected. Both the size and geometry of the CO-emitting region are determined by fitting a bidimensional Gaussian to the continuum-compensated CO bandhead visibilities. The CO-emitting region has a diameter of 2.74 +/-(0.08)(0.07) +/- 0.07 0.08 mas (1.16 +/- 0.03 au), and is located in the inner gaseous disc, well within the dusty rim, with inclination and PA matching the dusty disc geometry, which indicates that both dusty and gaseous discs are coplanar. Physical and dynamical gas conditions are inferred by modelling the CO spectrum. Finally, we derive a direct measurement of the stellar mass of M-* similar to 14.7(-3.6)(+2)M(circle dot) M * similar to 14 . 7 - 3.6 + 2 M circle dot by combining our interferometric and spectral modelling results.
2020
Authors
Lemos, FK; Cherri, AC; de Araujo, SA;
Publication
International Journal of Production Research
Abstract
The access to the final selection minute is only available to applicants.
Please check the confirmation e-mail of your application to obtain the access code.