When Reverse-Engineering Meets Side-Channel Analysis – Digital Lockpicking in Practice

Abstract

Abstract. In the past years, various electronic access control systems have been found to be insecure. In consequence, attacks have emerged that permit unauthorized access to secured objects. One of the few remaining, allegedly secure digital locking systems-the system 3060 manufactured and marketed by SimonsVoss-is employed in numerous objects worldwide. Following the trend to analyze the susceptibility of real-world products towards implementation attacks, we illustrate our approach to understand the unknown embedded system and its components. Detailed investigations are performed in a step-by-step process, including the analysis of the communication between transponder and lock, reverse-engineering of the hardware, bypassing the read-out protection of a microcontroller, and reverse-engineering the extracted program code. Piecing all parts together, the security mechanisms of the system can be completely circumvented by means of implementation attacks. We present an EM side-channel attack for extracting the secret system key from a door lock. This ultimately gives access to all doors of an entire installation. Our technique targets a proprietary function (used in combination with a DES for key derivation), probably originally implemented as an obscurity-based countermeasure to prevent attacks.

Fundamental Challenges Toward Making the IoT a Reachable Reality

“…Adding noise into the traces is an alternative approach, as the injected artifical noise makes information extraction more difficult for attackers [Demme et al 2012]. Another approach is to frequently derive and update key information such that the side-channel attacker cannot gather sufficient information for breaking the key value before the next key update [Oswald et al 2014;Xiao et al 2014]. Physical unclonable functions (PUFs) are an effective hardware security solution [Suh and Devadas 2007;Holcomb and Fu 2014]; however, side-channel attacks can still break PUFs [Rostami et al 2014].…”

Microcontrollers as (In)Security Devices for Pervasive Computing Applications

“…SCA has gained considerable attention since its introduction in 1996 [1]. One reason for this is that many realworld targets were broken due to their susceptibility to side-channel attacks (e.g., [10] and [12]- [15]).…”

“…The widespread digital locking system 3060 analyzed in [7] and [10] is based on an undisclosed, proprietary cryptographic protocol. The latest revision is termed ''Generation 2'' or ''G2-based'' system by the manufacturer.…”

“…Based on the reverseengineered protocol, both cryptanalytical and side-channel attacks were developed that allow an adversary to bypass the locking system and gain unauthorized access. Section V is based on the research presented in [7] and [10].…”

Robust profiled attacks: should the adversary trust the dataset?

“…The physical properties that can be extracted are, for examples, the execution time of a cryptographic algorithm [1], the electromagnetic emanation [2] or the power consumption of the device [3]. From an industrial point of view, side-channel attacks lead to extremely effective and successful attacks against (certified and uncertified) industrial products [4][5][6].…”