Biblio

Remote Attestation (RA) is a security service that detects malware presence on remote IoT devices by verifying their software integrity by a trusted party (verifier). There are three main types of RA: software (SW)-, hardware (HW)-, and hybrid (SW/HW)-based. Hybrid techniques obtain secure RA with minimal hardware requirements imposed on the architectures of existing microcontrollers units (MCUs). In recent years, considerable attention has been devoted to hybrid techniques since prior software-based ones lack concrete security guarantees in a remote setting, while hardware-based approaches are too costly for low-end MCUs. However, one key problem is that many already deployed IoT devices neither satisfy minimal hardware requirements nor support hardware modifications, needed for hybrid RA. This paper bridges the gap between software-based and hybrid RA by proposing a novel RA scheme based on software virtualization. In particular, it proposes a new scheme, called SIMPLE, which meets the minimal hardware requirements needed for secure RA via reliable software. SIMPLE depends on a formally-verified software-based memory isolation technique, called Security MicroVisor (Sμ V). Its reliability is achieved by extending the formally-verified safety and correctness properties to cover the entire software architecture of SIMPLE. Furthermore, SIMPLE is used to construct SIMPLE+, an efficient swarm attestation scheme for static and dynamic heterogeneous IoT networks. We implement and evaluate SIMPLE and SIMPLE+ on Atmel AVR architecture, a common MCU platform.

Modern automotive architectures are complex and often comprise of hundreds of electronic control units (ECUs). These ECUs provide diverse services including infotainment, telematics, diagnostics, advanced driving assistance, and many others. The availability of such services is mainly attained by the increasing connectivity with the external world, thus expanding the attack surface. In recent years, automotive original equipment manufacturers (OEMs) and ECU suppliers have become cautious of cyber attacks and have begun fortifying the most vulnerable systems, with hardware-based security modules that enable sandboxing, secure boot, secure software updates and end-to-end message authentication. Nevertheless, insecure legacy ECUs are still in-use in modern vehicles due to price and design complexity issues. Legacy ECUs depend on simple microcontrollers, that lack any kind of hardware-based security. This makes it essential to bridge the gap between modern and legacy ECUs through software-based security by which cyber attacks can be mitigated, thus enhancing the security of vehicles. This paper provides one more step towards highly secure vehicles by introducing a lightweight software- based security framework which provides legacy ECUs with software-based virtualization and protection features along with custom security services. We discuss the motivation for pure software-based approaches, explore the various requirements and advantages obtained, and give an initial insight of the design rationale. Furthermore, we provide a proof of concept implementation and evaluation with a demonstrative use case illustrating the importance of such framework in delivering new diagnostics security services to legacy ECUs.

Bare-metal microcontrollers are a family of Internet of Things (IoT) devices which are increasingly deployed in critical industrial environments. Similar to other IoT devices, bare-metal microcontrollers are vulnerable to memory corruption and code-reuse attacks. We propose MicroGuard, a novel mitigation method based on component-level sandboxing and automated code randomization to securely encapsulate application components in isolated environments. We implemented MicroGuard and evaluated its efficacy and efficiency with a real-world benchmark against different types of attacks. As our evaluation shows, MicroGuard provides better security than ACES, current state-of-the-art protection framework for bare-metal microcontrollers, with a comparable performance overhead.

The Internet of Things (IoT) consists of embedded devices that sense and manage our environment in a growing range of applications. Large-scale IoT systems such as smart cities require significant investment in both equipment and personnel. To maximize return on investment, IoT platforms should support multiple third-party applications and adaptation of infrastructure over time. Realizing the vision of shared IoT platforms demands strong security guarantees. That is particularly challenging considering the limited capability and resource constraints of many IoT devices. In this paper, we present SPEED, an approach to secure erasure with verifiability in IoT. Secure erasure is a fundamental property when it comes to share an IoT platform with other users which guarantees the cleanness of a device's memory at the beginning of the application deployment as well as at the time of releasing the underlying IoT device. SPEED relies on two security primitives: memory isolation and distance bounding protocol. We evaluate the performance of SPEED by implementing it on a simple bare-metal IoT device belongs to Class-1. Our evaluation results show a limited overhead in terms of memory footprint, time, and energy consumption.

The Internet of Things (IoT) promises to tackle a range of environmental challenges and deliver large efficiency gains in industry by embedding computational intelligence, sensing and control in our physical environment. Multiple independent parties are increasingly seeking to leverage shared IoT infrastructure, using a similar model to the cloud, and thus require constrained IoT devices to become microservice-hosting platforms that can securely and concurrently execute their code and interoperate. This vision demands that heterogeneous services, peripherals and platforms are provided with an expanded set of security guarantees to prevent third-party services from hijacking the platform, resource-level access control and accounting, and strong isolation between running processes to prevent unauthorized access to third-party services and data. This paper introduces Polyglot CerberOS, a resource-secure operating system for multi-tenant IoT devices that is realised through a reconfigurable virtual machine which can simultaneously execute interoperable services, written in different languages. We evaluate Polyglot CerberOS on IETF Class-1 devices running both Java and C services. The results show that interoperability and strong security guarantees for multilingual services on multi-tenant commodity IoT devices are feasible, in terms of performance and memory overhead, and transparent for developers.

The Internet of Things (IoT) creates value by connecting digital processes to the physical world using embedded sensors, actuators and wireless networks. The IoT is increasingly intertwined with critical industrial processes, yet contemporary IoT devices offer limited security features, creating a large new attack surface and inhibiting the adoption of IoT technologies. Hardware security modules address this problem, however, their use increases the cost of embedded IoT devices. Furthermore, millions of IoT devices are already deployed without hardware security support. This paper addresses this problem by introducing a Security MicroVisor (SμV) middleware, which provides memory isolation and custom security operations using software virtualisation and assembly-level code verification. We showcase SμV by implementing a key security feature: remote attestation. Evaluation shows extremely low overhead in terms of memory, performance and battery lifetime for a representative IoT device.