The first part of this paper discusses developments wrt. smart (electricity) meters (simply called E-meters) in general, with emphasis on security and privacy issues. The second part will be more technical and describes protocols for secure communication with E-meters and for fraud detection (leakage) in a privacy-preserving manner, using a combination of Paillier's additive homomorphic encryption and additive secret sharing.

Dynamic frequency and voltage scaling features have been introduced to manage ever-growing heat and power consumption in modern processors. Design restrictions ensure frequency and voltage are adjusted as a pair, based on the current load, because for each frequency there is only a certain voltage range where the processor can operate correctly. For this purpose, many processors (including the widespread Intel Core series) expose privileged software interfaces to dynamically regulate processor frequency and operating voltage. In this paper, we demonstrate that these privileged interfaces can be reliably exploited to undermine the system's security. We present the Plundervolt attack, in which a privileged software adversary abuses an undocumented Intel Core voltage scaling interface to corrupt the integrity of Intel SGX enclave computations. Plundervolt carefully controls the processor's supply voltage during an enclave computation, inducing predictable faults within the processor package. Consequently, even Intel SGX's memory encryption/authentication technology cannot protect against Plundervolt. In multiple case studies, we show how the induced faults in enclave computations can be leveraged in real-world attacks to recover keys from cryptographic algorithms (including the AES-NI instruction set extension) or to induce memory safety vulnerabilities into bug-free enclave code. We finally discuss why mitigating Plundervolt is not trivial, requiring trusted computing base recovery through microcode updates or hardware changes.

Abstract.The mifare Classic is a contactless smart card that is used extensively in access control for office buildings, payment systems for public transport, and other applications. We reverse engineered the security mechanisms of this chip: the authentication protocol, the symmetric cipher, and the initialization mechanism. We describe several security vulnerabilities in these mechanisms and exploit these vulnerabilities with two attacks; both are capable of retrieving the secret key from a genuine reader. The most serious one recovers the secret key from just one or two authentication attempts with a genuine reader in less than a second on ordinary hardware and without any pre-computation. Using the same methods, an attacker can also eavesdrop the communication between a tag and a reader, and decrypt the whole trace, even if it involves multiple authentications. This enables an attacker to clone a card or to restore a real card to a previous state.

Implantable Medical Devices (IMDs) typically use proprietary protocols with no or limited security to wirelessly communicate with a device programmer. These protocols enable doctors to carry out critical functions, such as changing the IMD's therapy or collecting telemetry data, without having to perform surgery on the patient. In this paper, we fully reverse-engineer the proprietary communication protocol between a device programmer and the latest generation of a widely used Implantable Cardioverter Defibrillator (ICD) which communicate over a long-range RF channel (from two to five meters). For this we follow a black-box reverse-engineering approach and use inexpensive Commercial Off-The-Shelf (COTS) equipment. We demonstrate that reverse-engineering is feasible by a weak adversary who has limited resources and capabilities without physical access to the devices. Our analysis of the proprietary protocol results in the identification of several protocol and implementation weaknesses. Unlike previous studies, which found no security measures, this article discovers the first known attempt to obfuscate the data that is transmitted over the air. Furthermore, we conduct privacy and Denial-of-Service (DoS) attacks and give evidence of other attacks that can compromise the patient's safety. All these attacks can be performed without needing to be in close proximity to the patient. We validate that our findings apply to (at least) 10 types of ICDs that are currently on the market. Finally, we propose several practical short-and long-term countermeasures to mitigate or prevent existing vulnerabilities.

This paper provides a formal framework for the analysis of information hiding properties of anonymous communication protocols in terms of epistemic logic. The key ingredient is our notion of observational equivalence, which is based on the cryptographic structure of messages and relations between otherwise random looking messages. Two runs are considered observationally equivalent if a spy cannot discover any meaningful distinction between them. We illustrate our approach by proving sender anonymity and unlinkability for two anonymizing protocols, Onion Routing and Crowds. Moreover, we consider a version of Onion Routing in which we inject a subtle error and show how our framework is capable of capturing this flaw.