Resilient Information Systems Security

Robustness and Transferability of Universal Attacks on Compressed Models

Neural network compression methods like pruning and quantization are very effective at efficiently deploying Deep Neural Networks (DNNs) on edge devices. However, DNNs remain vulnerable to adversarial examples-inconspicuous inputs that are specifically designed to fool these models. In particular, Universal Adversarial Perturbations (UAPs), are a powerful class of adversarial attacks which create adversarial perturbations that can generalize across a large set of inputs. In this work, we analyze the effect of various compression techniques to UAP attacks, including different forms of pruning and quantization. We test the robustness of compressed models to white-box and transfer attacks, comparing them with their […]

Hazard Driven Threat Modelling for Cyber Physical Systems

Adversarial actors have shown their ability to infiltrate enterprise networks deployed around Cyber Physical Systems (CPSs) through social engineering, credential stealing and file-less infections. When inside, they can gain enough privileges to maliciously call legitimate APIs and apply unsafe control actions to degrade the system performance and undermine its safety. Our work lies at the intersection of security and safety, and aims to understand dependencies among security, reliability and safety in CPS/IoT. We present a methodology to perform hazard driven threat modelling and impact assessment in the context of CPSs. The process starts from the analysis of behavioural, functional and […]

When can we trust cyber-physical systems?

Video of the presentation given in the Cyber security session of the Codex ‘World’s Top 50 Innovators’. The session also included presentations from Mikko Hypponen, Chief Research Officer, F-Secure, Andrew Rubin, CEO and Founder, Illumio, and Dave Palmer, Director of Technology, Darktrace as well as a panel discussion.  

Tracking the Bad Guys: An Efficient Forensic Methodology To Trace Multi-step Attacks Using Core Attack Graphs

Tracking the Bad Guys: An Efficient Forensic Methodology To Trace Multi-step Attacks Using Core Attack Graphs, has been presented at the 13th IEEE/IFIP International Conference on Network and Service Management (CNSM’17), November 2017, in Tokyo, Japan.   The paper is available here and the presentation slides (PDF) can be downloaded here. Authors: Martín Barrère, Rodrigo Vieira Steiner, Rabih Mohsen, Emil C. Lupu In this paper, we describe an efficient methodology to guide investigators during network forensic analysis. To this end, we introduce the concept of core attack graph, a compact representation of the main routes an attacker can take towards […]

Naggen: a Network Attack Graph GENeration Tool

Naggen: a Network Attack Graph GENeration Tool, has been presented at the IEEE Conference on Communications and Network Security (CNS’17), October 2017, in Las Vegas, USA. The paper is available here and the poster can be downloaded here. Authors: Martín Barrère, Emil C. Lupu Attack graphs constitute a powerful security tool aimed at modelling the many ways in which an attacker may compromise different assets in a network. Despite their usefulness in several security-related activities (e.g. hardening, monitoring, forensics), the complexity of these graphs can massively grow as the network becomes denser and larger, thus defying their practical usability. In […]

Argumentation-based Security for Social Good

The paper “Argumentation-based Security for Social Good” presented at the AAAI Spring Symposia 2017 is now available at the AAAI Technical Report. Title: Argumentation-Based Security for Social Good Authors: Erisa Karafili, Antonis C. Kakas, Nikolaos I. Spanoudakis, Emil C. Lupu Abstract: The increase of connectivity and the impact it has in ever day life is raising new and existing security problems that are becoming important for social good. We introduce two particular problems: cyber attack attribution and regulatory data sharing. For both problems, decisions about which rules to apply, should be taken under incomplete and context dependent information. The solution […]