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  1. Perumalla, Kalyan ; Lopez Jr., Juan ; Siraj, Ambareen (Ed.)
    Executable steganography, the hiding of software machine code inside of a larger program, is a potential approach to introduce new software protection constructs such as watermarks or fingerprints. Software fingerprinting is, therefore, a process similar to steganography, hiding data within other data. The goal of fingerprinting is to hide a unique secret message, such as a serial number, into copies of an executable program in order to provide proof of ownership of that program. Fingerprints are a special case of watermarks, with the difference being that each fingerprint is unique to each copy of a program. Traditionally, researchers describe four aims that a software fingerprint should achieve. These include the fingerprint should be difficult to remove, it should not be obvious, it should have a low false positive rate, and it should have negligible impact on performance. In this research, we propose to extend these objectives and introduce a fifth aim: that software fingerprints should be machine independent. As a result, the same fingerprinting method can be used regardless of the architecture used to execute the program. Hence, this paper presents an approach towards the realization of machine-independent fingerprinting of executable programs. We make use of Low-Level Virtual Machine (LLVM) intermediate representation during the software compilation process to demonstrate both a simple static fingerprinting method as well as a dynamic method, which displays our aim of hardware independent fingerprinting. The research contribution includes a realization of the approach using the LLVM infrastructure and provides a proof of concept for both simple static and dynamic watermarks that are architecture neutral. 
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  2. null (Ed.)
    Geospatial technologies and geographic methods are foundational skills in modern water resources monitoring, research, management, and policy-making. Understanding and sustaining healthy water resources depends on spatial awareness of watersheds, land use, hydrologic networks, and the communities that depend on these resources. Water professionals across disciplines are expected to have familiarity with hydrologic geospatial data. Proficiency in spatial thinking and competency reading hydrologic maps are essential skills. In addition, climate change and non-stationary ecological conditions require water specialists to utilize dynamic, time-enabled spatiotemporal datasets to examine shifting patterns and changing environments. Future water specialists will likely require even more advanced geospatial knowledge with the implementation of distributed internet-of-things sensor networks and the collection of mobility data. To support the success of future water professionals and increase hydrologic awareness in our broader communities, teachers in higher education must consider how their curriculum provides students with these vital geospatial skills. This paper considers pedagogical perspectives from educators with expertise in remote sensing, geomorphology, human geography, environmental science, ecology, and private industry. These individuals share a wealth of experience teaching geographic techniques such as GIS, remote sensing, and field methods to explore water resources. The reflections of these educators provide a snapshot of current approaches to teaching water and geospatial techniques. This commentary captures faculty experiences, ambitions, and suggestions for teaching at this moment in time. 
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  3. Securing applications on untrusted platforms can involve protection against legitimate end-users who act in the role of malicious reverse engineers and hackers. Such adversaries have access to the full execution environment of programs, whether the program comes in the form of software or hardware. In this paper, we consider the nature of obfuscating algorithms that perform iterative, step-wise transformation of programs into more complex forms that are intended to increase the complexity (time, resources) for malicious reverse engineers. We consider simple Boolean logic programs as the domain of interest and examine a specific transformation technique known as iterative sub-circuit selection and replacement (ISR), which represents a practical, syntactic approach for obfuscation. Specifically, we focus on improving the security of ISR by maximizing the flexibility and potential security of the replacement step of the algorithm which can be formulated in the following question: given a selection of Boolean logic gates (i.e., a sub-circuit), how can we produce a semantically equivalent (polymorphic) version of the sub-circuit such that the distribution of potential replacements represents a random, uniform distribution from the set of all possible replacements. This practical question is related to the theoretic study of indistinguishability obfuscation, where a transformer for a class of circuits guarantees that given any two semantically equivalent circuits from the class, the distribution of variants from their obfuscation are computationally indistinguishable. Ideally, polymorphic circuits that follow a random, uniform distribution provide stronger protection against malicious analyzers that target identification of distinct patterns as a basis for deobfuscation and simplification. In this paper, we introduce a novel approach for polymorphic circuit replacement called random Boolean logic expansion (RBLE), which applies Boolean logic laws (of reduction) in reverse. We compare this approach against another proposed method of polymorphic replacement that relies on static circuit libraries. As a contribution, we show the strengths and weaknesses of each approach, examine initial results from empirical studies to estimate the uniformity of polymorphic distributions, and provide the argument for how such algorithms can be readily applied in software contexts. RBLE provides a unique method to generate polymorphic variants of arbitrary input, output, and gate size. We report initial findings for studying variants produced by this method and, from empirical evaluation, show that RBLE has promise for generating distributions of unique, uniform circuits when size is unconstrained, but for targeted size distributions, the approach requires some adjustment in order to reach potential circuit variants. 
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  4. Malware authors make use of several techniques to obfuscate code from reverse engineering tools such as IdaPro. Typically, these techniques tend to be effective for about three to six instructions, but eventually the tools can properly disassemble the remaining code once the tool is again synchronized with the operation codes. But this loss of synchronization can be used to hide information within the instructions – steganography. Our research explores an approach to this by presenting “Weaver”, a framework for executable steganography. “Weaver” differs from other techniques in how it hides malicious instructions: the hiding instructions are prepared by generating an assembly listing of the program and finding candidate hiding locations, the steganography instructions are prepared by creating an assembly listing of the program to obtain the operation codes to be hidden, and the “weaving” process merges the two. This “weaving” attempts to place all the steganography instructions into candidate locations found in the hiding instructions. 
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