Runtime protection via dataflow flattening

Software running on an open architecture, such as the PC, is vulnerable to inspection and modification. Since software may process valuable or sensitive information, many defenses against data analysis and modification have been proposed. This paper complements existing work and focuses on hiding data location throughout program execution. To achieve this, we combine three techniques: (i) periodic reordering of the heap, (ii) migrating local variables from the stack to the heap and (iii) pointer scrambling. By essentialy flattening the dataflow graph of the program, the techniques serve to complicate static dataflow analysis and dynamic data tracking. Our methodology can be viewed as a data-oriented analogue of control-flow flattening techniques. Dataflow flattening is useful in practical scenarios like DRM, information-flow protection, and exploit resistance. Our prototype implementation compiles C programs into a binary for which every access to the heap is redirected through a memory management unit. Stack-based variables may be migrated to the heap, while pointer accesses and arithmetic may be scrambled and redirected. We evaluate our approach experimentally on the SPEC CPU2006 benchmark suit

FPGA based remote code integrity verification of programs in distributed embedded systems

The explosive growth of networked embedded systems has made ubiquitous and pervasive computing a reality. However, there are still a number of new challenges to its widespread adoption that include scalability, availability, and, especially, security of software. Among the different challenges in software security, the problem of remote-code integrity verification is still waiting for efficient solutions. This paper proposes the use of reconfigurable computing to build a consistent architecture for generation of attestations (proofs) of code integrity for an executing program as well as to deliver them to the designated verification entity. Remote dynamic update of reconfigurable devices is also exploited to increase the complexity of mounting attacks in a real-word environment. The proposed solution perfectly fits embedded devices that are nowadays commonly equipped with reconfigurable hardware components that are exploited to solve different computational problems

Towards a unified software attack model to assess software protections

Attackers can tamper with programs to break usage conditions. Different software protection techniques have been proposed to limit the possibility of tampering. Some of them just limit the possibility to understand the (binary) code, others react more actively when a change attempt is detected. However, the validation of the software protection techniques has been always conducted without taking into consideration a unified process adopted by attackers to tamper with programs. In this paper we present an extension of the mini-cycle of change, initially proposed to model the process of changing program for maintenance, to describe the process faced by an attacker to defeat software protections. This paper also shows how this new model should support a developer when considering what are the most appropriate protections to deplo

Examining GPS monitoring alerts triggered by sex offenders: The divergence of legislative goals and practical application in community corrections

Purpose Legislative mandates that require GPS monitoring of offenders add to the existing logistical complexities of community supervision. Challenges in implementing GPS policies and practices are heightened by the lack of sound empirical research. Studies examining the relationships between GPS monitoring of sex offenders in the community and the legislative goals of public safety, deterrence, and cost effectiveness are virtually nonexistent. To begin to address this gap in the literature, this study examines the impact of a statutorily-based GPS monitoring program for adult sex offenders convicted of dangerous crimes against children and placed under community supervision. Method Official offender generated alert data for DCAC Sex Offenders in Maricopa County, AZ are examined from the time of legislative mandate for a subsequent two year period. Results Analyses highlight the significant number of equipment related alerts triggered by a loss of satellite signal for offenders under GPS monitoring as a key concern as well as a significant increase in officer workload as a result. Conclusions A divergence between legislative goals and practical application of mandated GPS monitoring programs exists. GPS technology is far more limited than anticipated and should be viewed as a tool rather than depended upon as a control mechanism

Reactive attestation : automatic detection and reaction to software tampering attacks

Anti-tampering is a form of software protection conceived to detect and avoid the execution of tampered programs. tamper detection assesses programs’ integrity with load- or execution-time checks. Avoidance reacts to tampered programs by stopping or rendering them unusable. General purpose reactions (such as halting the execution) stand out like a lighthouse in the code and are quite easy to defeat by an attacker. More sophisticated reactions, which degrade the user experience or the quality of service, are less easy to locate and remove but are too tangled with the program’s business logic, and are thus difficult to automate by a general purpose protection tool. In the present paper, we propose a novel approach to antitampering that (i) fully automatically applies to a target program, (ii) uses Remote Attestation for detection purposes and (iii) adopts a server-side reaction that is difficult to block by an attacker. By means of Client/Server Code Splitting, a crucial part of the program is removed from the client and executed on a remote trusted server in sync with the client. If a client program provides evidences of its integrity, the part moved to the server is executed. Otherwise, a server-side reaction logic may (temporarily or definitely) decide to stop serving it. Therefore, a tampered client application can not continue its execution. We assessed our automatic protection tool on a case study Android application. Experimental results show that all the original and tampered executions are correctly detected, reactions are promptly applied, and execution overhead is on an acceptable level

Resilient networking in wireless sensor networks

This report deals with security in wireless sensor networks (WSNs), especially in network layer. Multiple secure routing protocols have been proposed in the literature. However, they often use the cryptography to secure routing functionalities. The cryptography alone is not enough to defend against multiple attacks due to the node compromise. Therefore, we need more algorithmic solutions. In this report, we focus on the behavior of routing protocols to determine which properties make them more resilient to attacks. Our aim is to find some answers to the following questions. Are there any existing protocols, not designed initially for security, but which already contain some inherently resilient properties against attacks under which some portion of the network nodes is compromised? If yes, which specific behaviors are making these protocols more resilient? We propose in this report an overview of security strategies for WSNs in general, including existing attacks and defensive measures. In this report we focus at the network layer in particular, and an analysis of the behavior of four particular routing protocols is provided to determine their inherent resiliency to insider attacks. The protocols considered are: Dynamic Source Routing (DSR), Gradient-Based Routing (GBR), Greedy Forwarding (GF) and Random Walk Routing (RWR)

Trade-offs between Distributed Ledger Technology Characteristics

When developing peer-to-peer applications on distributed ledger technology (DLT), a crucial decision is the selection of a suitable DLT design (e.g., Ethereum), because it is hard to change the underlying DLT design post hoc. To facilitate the selection of suitable DLT designs, we review DLT characteristics and identify trade-offs between them. Furthermore, we assess how DLT designs account for these trade-offs and we develop archetypes for DLT designs that cater to specific requirements of applications on DLT. The main purpose of our article is to introduce scientific and practical audiences to the intricacies of DLT designs and to support development of viable applications on DLT