Yuri Gil Dantas

Yuri Gil Dantas, Vivek Nigam, Harald Ruess

The ISO 21434 is a new standard that has been proposed to address the future challenges of automotive cybersecurity. This white paper takes a closer look at the ISO 21434 helping engineers to understand the ISO 21434 parts, the key activities to be carried out and the main artefacts that shall be produced. As any certification, obtaining the ISO 21434 certification can be daunting at first sight. Engineers have to deploy processes that include several security risk assessment methods to produce security arguments and evidence supporting item security claims. In this white paper, we propose a security engineering approach that can ease this process by relying on Rigorous Security Assessments and Incremental Assessment Maintenance methods supported by automation. We demonstrate by example that the proposed approach can greatly increase the quality of the produced artefacts, the efficiency to produce them, as well as enable continuous security assessment. Finally, we point out some key research directions that we are investigating to fully realize the proposed approach.

Yuri Gil Dantas, Antoaneta Kondeva, Vivek Nigam

The development of safety-critical systems requires the control of hazards that can potentially cause harm. To this end, safety engineers rely during the development phase on architectural solutions, called safety patterns, such as safety monitors, voters, and watchdogs. The goal of these patterns is to control (identified) faults that can trigger hazards. Safety patterns can control such faults by e.g., increasing the redundancy of the system. Currently, the reasoning of which pattern to use at which part of the target system to control which hazard is documented mostly in textual form or by means of models, such as GSN-models, with limited support for automation. This paper proposes the use of logic programming engines for the automated reasoning about system safety. We propose a domain-specific language for embedded system safety and specify as disjunctive logic programs reasoning principles used by safety engineers to deploy safety patterns, e.g., when to use safety monitors, or watchdogs. Our machinery enables two types of automated safety reasoning: (1) identification of which hazards can be controlled and which ones cannot be controlled by the existing safety patterns; and (2) automated recommendation of which patterns could be used at which place of the system to control potential hazards. Finally, we apply our machinery to two examples taken from the automotive domain: an adaptive cruise control system and a battery management system.

Marcilio O. O. Lemos, Yuri Gil Dantas, Iguatemi E. Fonseca et al.

Telephony Denial of Service (TDoS) attacks target telephony services, such as Voice over IP (VoIP), not allowing legitimate users to make calls. There are few defenses that attempt to mitigate TDoS attacks, most of them using IP filtering, with limited applicability. In our previous work, we proposed to use selective strategies for mitigating HTTP Application-Layer DDoS Attacks demonstrating their effectiveness in mitigating different types of attacks. Developing such types of defenses is challenging as there are many design options, eg, which dropping functions and selection algorithms to use. Our first contribution is to demonstrate both experimentally and by using formal verification that selective strategies are suitable for mitigating TDoS attacks. We used our formal model to help decide which selective strategies to use with much less effort than carrying out experiments. Our second contribution is a detailed comparison of the results obtained from our formal models and the results obtained by carrying out experiments. We demonstrate that formal methods is a powerful tool for specifying defenses for mitigating Distributed Denial of Service attacks allowing to increase our confidence on the proposed defense before actual implementation.