Biblio

Malware authors attempt to obfuscate and hide their code in its static and dynamic states. This paper provides a novel approach to aid analysis by intercepting and capturing malware artifacts and providing dynamic control of process flow. Capturing malware artifacts allows an analyst to more quickly and comprehensively understand malware behavior and obfuscation techniques and doing so interactively allows multiple code paths to be explored. The faster that malware can be analyzed the quicker the systems and data compromised by it can be determined and its infection stopped. This research proposes an instantiation of an interactive malware analysis and artifact capture tool.

Program analyses necessarily make approximations that often lead them to report true alarms interspersed with many false alarms. We propose a new approach to leverage user feedback to guide program analyses towards true alarms and away from false alarms. Our approach associates each alarm with a confidence value by performing Bayesian inference on a probabilistic model derived from the analysis rules. In each iteration, the user inspects the alarm with the highest confidence and labels its ground truth, and the approach recomputes the confidences of the remaining alarms given this feedback. It thereby maximizes the return on the effort by the user in inspecting each alarm. We have implemented our approach in a tool named Bingo for program analyses expressed in Datalog. Experiments with real users and two sophisticated analyses–-a static datarace analysis for Java programs and a static taint analysis for Android apps–-show significant improvements on a range of metrics, including false alarm rates and number of bugs found.

The detection of bugs in software systems has been divided into two research areas: static code analysis and statistical modeling of historical data. Static analysis indicates precise problems on line numbers but has the disadvantage of suggesting many warning which are often false positives. In contrast, statistical models use the history of the system to suggest which files or commits are likely to contain bugs. These course-grained predictions do not indicate to the developer the precise reasons for the bug prediction. We combine static analysis with statistical bug models to limit the number of warnings and provide specific warnings information at the line level. Previous research was able to process only a limited number of releases, our tool, WarningsGuru, can analyze all commits in a source code repository and we currently have processed thousands of commits and warnings. Since we process every commit, we present developers with more precise information about when a warning is introduced allowing us to show recent warnings that are introduced in statistically risky commits. Results from two OSS projects show that CommitGuru's statistical model flags 25% and 29% of all commits as risky. When we combine this with static analysis in WarningsGuru the number of risky commits with warnings is 20% for both projects and the number commits with new warnings is only 3% and 6%. We can drastically reduce the number of commits and warnings developers have to examine. The tool, source code, and demo is available at https://github.com/louisq/warningsguru.

Early detection of new kinds of malware always plays an important role in defending the network systems. Especially, if intelligent protection systems could themselves detect an existence of new malware types in their system, even with a very small number of malware samples, it must be a huge benefit for the organization as well as the social since it help preventing the spreading of that kind of malware. To deal with learning from few samples, term ``one-shot learning'' or ``fewshot learning'' was introduced, and mostly used in computer vision to recognize images, handwriting, etc. An approach introduced in this paper takes advantage of One-shot learning algorithms in solving the malware classification problem by using Memory Augmented Neural Network in combination with malware's API calls sequence, which is a very valuable source of information for identifying malware behavior. In addition, it also use some advantages of the development in Natural Language Processing field such as word2vec, etc. to convert those API sequences to numeric vectors before feeding to the one-shot learning network. The results confirm very good accuracies compared to the other traditional methods.

While the rapid adaptation of mobile devices changes our daily life more conveniently, the threat derived from malware is also increased. There are lots of research to detect malware to protect mobile devices, but most of them adopt only signature-based malware detection method that can be easily bypassed by polymorphic and metamorphic malware. To detect malware and its variants, it is essential to adopt behavior-based detection for efficient malware classification. This paper presents a system that classifies malware by using common behavioral characteristics along with malware families. We measure the similarity between malware families with carefully chosen features commonly appeared in the same family. With the proposed similarity measure, we can classify malware by malware's attack behavior pattern and tactical characteristics. Also, we apply community detection algorithm to increase the modularity within each malware family network aggregation. To maintain high classification accuracy, we propose a process to derive the optimal weights of the selected features in the proposed similarity measure. During this process, we find out which features are significant for representing the similarity between malware samples. Finally, we provide an intuitive graph visualization of malware samples which is helpful to understand the distribution and likeness of the malware networks. In the experiment, the proposed system achieved 97% accuracy for malware classification and 95% accuracy for prediction by K-fold cross-validation using the real malware dataset.

In this paper we present a new approach, named DLGraph, for malware detection using deep learning and graph embedding. DLGraph employs two stacked denoising autoencoders (SDAs) for representation learning, taking into consideration computer programs' function-call graphs and Windows application programming interface (API) calls. Given a program, we first use a graph embedding technique that maps the program's function-call graph to a vector in a low-dimensional feature space. One SDA in our deep learning model is used to learn a latent representation of the embedded vector of the function-call graph. The other SDA in our model is used to learn a latent representation of the given program's Windows API calls. The two learned latent representations are then merged to form a combined feature vector. Finally, we use softmax regression to classify the combined feature vector for predicting whether the given program is malware or not. Experimental results based on different datasets demonstrate the effectiveness of the proposed approach and its superiority over a related method.

The similarity detection of the program has important significance in code reuse, plagiarism detection, intellectual property protection and information retrieval methods. Attribute counting methods cannot take into account program semantics. The method based on syntax tree or graph structure has a very high construction cost and low space efficiency. So it is difficult to solve problems in large-scale software systems. This paper uses different decision strategies for different levels, then puts forward a similarity detection method at the file level. This method can make full use of the features of the program and take into account the space-time efficiency. By using static analysis methods, we get function features and control flow features of files. And based on this, we establish the function call graph. The similar degree between two files can be measured with the two graphs. Experimental results show the method can effectively detect similar files. Finally, this paper discusses the direction of development of this method.

Data dependency flow have been reformulated as Context Free Grammar (CFG) reachability problem, and the idea was explored in detection of some web vulnerabilities, particularly Cross Site Scripting (XSS) and Access Control. However, reformulation of SQL Injection Vulnerability (SQLIV) detection as grammar reachability problem has not been investigated. In this paper, concepts of data dependency flow was used to reformulate SQLIVs detection as a CFG reachability problem. The paper, consequently defines reachability analysis strategy for SQLIVs detection.

Role-Based Access Control (RBAC) is often used in web applications to restrict operations and protect security sensitive information and resources. Web applications regularly undergo maintenance and evolution and their security may be affected by source code changes between releases. To prevent security regression and vulnerabilities, developers have to take re-validation actions before deploying new releases. This may become a significant undertaking, especially when quick and repeated releases are sought. We define protection-impacting changes as those changed statements during evolution that alter privilege protection of some code. We propose an automated method that identifies protection-impacting changes within all changed statements between two versions. The proposed approach compares statically computed security protection models and repository information corresponding to different releases of a system to identify protection-impacting changes. Results of experiments present the occurrence of protection-impacting changes over 210 release pairs of WordPress, a PHP content management web application. First, we show that only 41% of the release pairs present protection-impacting changes. Second, for these affected release pairs, protection-impacting changes can be identified and represent a median of 47.00 lines of code, that is 27.41% of the total changed lines of code. Over all investigated releases in WordPress, protection-impacting changes amounted to 10.89% of changed lines of code. Conversely, an average of about 89% of changed source code have no impact on RBAC security and thus need no re-validation nor investigation. The proposed method reduces the amount of candidate causes of protection changes that developers need to investigate. This information could help developers re-validate application security, identify causes of negative security changes, and perform repairs in a more effective way.

DLR as research organization increasingly faces the task to share its self-developed software with partners or publish openly. Hence, it is very important to harden the softwares to avoid opening attack vectors. Especially since DLR software is typically not developed by software engineering or security experts. In this paper we describe the data-oriented approach of our new found secure software engineering group to improve the software development process towards more secure software. Therefore, we have a look at the automated security evaluation of software as well as the possibilities to capture information about the development process. Our aim is to use our information sources to improve software development processes to produce high quality secure software.

The increasing amount of malware variants seen in the wild is causing problems for Antivirus Software vendors, unable to keep up by creating signatures for each. The methods used to develop a signature, static and dynamic analysis, have various limitations. Machine learning has been used by Antivirus vendors to detect malware based on the information gathered from the analysis process. However, adversarial examples can cause machine learning algorithms to miss-classify new data. In this paper we describe a method for malware analysis by converting malware binaries to images and then preparing those images for training within a Generative Adversarial Network. These unsupervised deep neural networks are not susceptible to adversarial examples. The conversion to images from malware binaries should be faster than using dynamic analysis and it would still be possible to link malware families together. Using the Generative Adversarial Network, malware detection could be much more effective and reliable.

Recent research suggests that 88% of Android applications that use Java cryptographic APIs make at least one mistake, which results in an insecure implementation. It is unclear, however, if these mistakes originate from code written by application or third-party library developers. Understanding the responsible party for a misuse case is important for vulnerability disclosure. In this paper, we bridge this knowledge gap and introduce source attribution to the analysis of cryptographic API misuse. We developed BinSight, a static program analyzer that supports source attribution, and we analyzed 132K Android applications collected in years 2012, 2015, and 2016. Our results suggest that third-party libraries are the main source of cryptographic API misuse. In particular, 90% of the violating applications, which contain at least one call-site to Java cryptographic API, originate from libraries. When compared to 2012, we found the use of ECB mode for symmetric ciphers has significantly decreased in 2016, for both application and third-party library code. Unlike application code, however, third-party libraries have significantly increased their reliance on static encryption keys for symmetric ciphers and static IVs for CBC mode ciphers. Finally, we found that the insecure RC4 and DES ciphers were the second and the third most used ciphers in 2016.

Parfait [1] is a static analysis tool originally developed to find implementation defects in C/C++ systems code. Parfait's focus is on proving both high precision (low false positives) as well as scaling to systems with millions of lines of code (typically requiring 10 minutes of analysis time per million lines). Parfait has since been extended to detect security vulnerabilities in applications code, supporting the Java EE and PL/SQL server stack. In this abstract we describe some of the challenges we encountered in this process including some of the differences seen between the applications code being analysed, our solutions that enable us to analyse a variety of applications, and a summary of the challenges that remain.

The number of new malware and new malware variants have been increasing continuously. Security experts analyze malware to capture the malicious properties of malware and to generate signatures or detection rules, but the analysis overheads keep increasing with the increasing number of malware. To analyze a large amount of malware, various kinds of automatic analysis methods are in need. Recently, deep learning techniques such as convolutional neural network (CNN) and recurrent neural network (RNN) have been applied for malware classifications. The features used in the previous approches are mostly based on API (Application Programming Interface) information, and the API invocation information can be obtained through dynamic analysis. However, the invocation information may not reflect malicious behaviors of malware because malware developers use various analysis avoidance techniques. Therefore, deep learning-based malware analysis using other features still need to be developed to improve malware analysis performance. In this paper, we propose a malware classification method using the deep learning algorithm based on byte information. Our proposed method uses images generated from malware byte information that can reflect malware behavioral context, and the convolutional neural network-based sentence analysis is used to process the generated images. We performed several experiments to show the effecitveness of our proposed method, and the experimental results show that our method showed higher accuracy than the naive CNN model, and the detection accuracy was about 99%.

This paper aims to explain static analysis techniques in detail, and to highlight the weaknesses and challenges which face it. To this end, more than 80 static analysis-based framework have been studied, and in their light, the process of detecting malicious applications has been divided into four phases that were explained in a schematic manner. Also, the features that is used in static analysis were discussed in detail by dividing it into four categories namely, Manifest-based features, code-based features, semantic features and app's metadata-based features. Also, the challenges facing methods based on static analysis were discussed in detail. Finally, a case study was conducted to test the strength of some known commercial antivirus and one of the stat-of-art academic static analysis frameworks against obfuscation techniques used by developers of malicious applications. The results showed a significant impact on the performance of the most tested antiviruses and frameworks, which is reflecting the urgent need for more accurately tools.

We present the concept of Just-In-Time (JIT) static analysis that interleaves code development and bug fixing in an integrated development environment. Unlike traditional batch-style analysis tools, a JIT analysis tool presents warnings to code developers over time, providing the most relevant results quickly, and computing less relevant results incrementally later. In this paper, we describe general guidelines for designing JIT analyses. We also present a general recipe for transforming static data-flow analyses to JIT analyses through a concept of layered analysis execution. We illustrate this transformation through CHEETAH, a JIT taint analysis for Android applications. Our empirical evaluation of CHEETAH on real-world applications shows that our approach returns warnings quickly enough to avoid disrupting the normal workflow of developers. This result is confirmed by our user study, in which developers fixed data leaks twice as fast when using CHEETAH compared to an equivalent batch-style analysis.

This paper presents Themis, an end-to-end static analysis tool for finding resource-usage side-channel vulnerabilities in Java applications. We introduce the notion of epsilon-bounded non-interference, a variant and relaxation of Goguen and Meseguer's well-known non-interference principle. We then present Quantitative Cartesian Hoare Logic (QCHL), a program logic for verifying epsilon-bounded non-interference. Our tool, Themis, combines automated reasoning in CHL with lightweight static taint analysis to improve scalability. We evaluate Themis on well known Java applications and demonstrate that Themis can find unknown side-channel vulnerabilities in widely-used programs. We also show that Themis can verify the absence of vulnerabilities in repaired versions of vulnerable programs and that Themis compares favorably against Blazer, a state-of-the-art static analysis tool for finding timing side channels in Java applications.

Most static analyzers are monolithic applications that define their own ways to analyze source code and present the results. Therefore aggregating multiple static analyzers into a single tool or integrating a new analyzer into existing tools requires a significant amount of effort. Over the last few years, we cultivated Renraku — a static analysis model that acts as a mediator between the static analyzers and the tools that present the reports. When used by both analysis and tool developers, this single quality model can reduce the cost to both introduce a new type of analysis to existing tools and create a tool that relies on existing analyzers.

Comparison of two binary files has many practical applications: the ability to detect programmatic changes between two versions, the ability to find old versions of statically linked libraries to prevent the use of well-known bugs, malware analysis, etc. In this article, a framework for comparison of binary files is presented. Framework uses IdaPro [1] disassembler and Binnavi [2] platform to recover structure of the target program and represent it as a call graph (CG). A program dependence graph (PDG) corresponds to each vertex of the CG. The proposed comparison algorithm consists of two main stages. At the first stage, several heuristics are applied to find the exact matches. Two functions are matched if at least one of the calculated heuristics is the same and unique in both binaries. At the second stage, backward and forward slicing is applied on matched vertices of CG to find further matches. According to empiric results heuristic method is effective and has high matching quality for unchanged or slightly modified functions. As a contradiction, to match heavily modified functions, binary code clone detection is used and it is based on finding maximum common subgraph for pair of PDGs. To achieve high performance on extensive binaries, the whole matching process is parallelized. The framework is tested on the number of real world libraries, such as python, openssh, openssl, libxml2, rsync, php, etc. Results show that in most cases more than 95% functions are truly matched. The tool is scalable due to parallelization of functions matching process and generation of PDGs and CGs.

In order to achieve a higher reusability and testability, static analyses are increasingly being build as modular pipelines of analysis components. However, to build, debug, test, and evaluate these components the complete pipeline has to be executed every time. This process recomputes intermediate results which have already been computed in a previous run but are lost because the preceding process ended and removed them from memory. We propose to leverage runtime reusability for static analysis pipelines and introduce SootKeeper, a framework to modularize static analyses into OSGi (Open Service Gateway initiative) bundles, which takes care of the automatic caching of intermediate results. Little to no change to the original analysis is necessary to use SootKeeper while speeding up the execution of code-build-debug cycles or evaluation pipelines significantly.

A program exhibits trigger-based behavior if it performs undocumented, often malicious, functions when the environmental conditions and/or specific input values match some pre-specified criteria. Checking whether such hidden functions exist in the program is important for increasing trustworthiness of software. In this paper, we propose a framework to effectively detect trigger-based behavior at the source code level. Our approach is semi-automated: We use automated source code instrumentation and mixed concrete and symbolic execution to generate potentially suspicious test cases that may trigger hidden, potentially malicious functions. The test cases must be investigated by a human analyst manually to decide which of them are real triggers. While our approach is not fully automated, it greatly reduces manual work by allowing analysts to focus on a few test cases found by our automated tools.

A smart grid is a fully automated power electricity network, which operates, protects and controls all its physical environments of power electricity infrastructure being able to supply energy in an efficient and reliable way. As the importance of cyber-physical system (CPS) security is growing, various vulnerability analysis methodologies for general systems have been suggested, whereas there has been few practical research targeting the smart grid infrastructure. In this paper, we highlight the significance of security vulnerability analysis in the smart grid environment. Then we introduce various automated vulnerability analysis techniques from executable files. In our approach, we propose a novel binary-based vulnerability discovery method for AMI and EV charging system to automatically extract security-related features from the embedded software. Finally, we present the test result of vulnerability discovery applied for AMI and EV charging system in Korean smart grid environment.

Ensuring software security is essential for developing a reliable software. A software can suffer from security problems due to the weakness in code constructs during software development. Our goal is to relate software security with different code constructs so that developers can be aware very early of their coding weaknesses that might be related to a software vulnerability. In this study, we chose Java nano-patterns as code constructs that are method-level patterns defined on the attributes of Java methods. This study aims to find out the correlation between software vulnerability and method-level structural code constructs known as nano-patterns. We found the vulnerable methods from 39 versions of three major releases of Apache Tomcat for our first case study. We extracted nano-patterns from the affected methods of these releases. We also extracted nano-patterns from the non-vulnerable methods of Apache Tomcat, and for this, we selected the last version of three major releases (6.0.45 for release 6, 7.0.69 for release 7 and 8.0.33 for release 8) as the non-vulnerable versions. Then, we compared the nano-pattern distributions in vulnerable versus non-vulnerable methods. In our second case study, we extracted nano-patterns from the affected methods of three vulnerable J2EE web applications: Blueblog 1.0, Personalblog 1.2.6 and Roller 0.9.9, all of which were deliberately made vulnerable for testing purpose. We found that some nano-patterns such as objCreator, staticFieldReader, typeManipulator, looper, exceptions, localWriter, arrReader are more prevalent in affected methods whereas some such as straightLine are more vivid in non-affected methods. We conclude that nano-patterns can be used as the indicator of vulnerability-proneness of code.

In recent years, with the advances in JavaScript engines and the adoption of HTML5 APIs, web applications begin to show a tendency to shift their functionality from the server side towards the client side, resulting in dense and complex interactions with HTML documents using the Document Object Model (DOM). As a consequence, client-side vulnerabilities become more and more prevalent. In this paper, we focus on DOM-sourced Cross-site Scripting (XSS), which is a kind of severe but not well-studied vulnerability appearing in browser extensions. Comparing with conventional DOM-based XSS, a new attack surface is introduced by DOM-sourced XSS where the DOM could become a vulnerable source as well besides common sources such as URLs and form inputs. To discover such vulnerability, we propose a detecting framework employing hybrid analysis with two phases. The first phase is the lightweight static analysis consisting of a text filter and an abstract syntax tree parser, which produces potential vulnerable candidates. The second phase is the dynamic symbolic execution with an additional component named shadow DOM, generating a document as a proof-of-concept exploit. In our large-scale real-world experiment, 58 previously unknown DOM-sourced XSS vulnerabilities were discovered in user scripts of the popular browser extension Greasemonkey.

The security of computer programs and systems is a very critical issue. With the number of attacks launched on computer networks and software, businesses and IT professionals are taking steps to ensure that their information systems are as secure as possible. However, many programmers do not think about adding security to their programs until their projects are near completion. This is a major mistake because a system is as secure as its weakest link. If security is viewed as an afterthought, it is highly likely that the resulting system will have a large number of vulnerabilities, which could be exploited by attackers. One of the reasons programmers overlook adding security to their code is because it is viewed as a complicated or time-consuming process. This paper presents a tool that will help programmers think more about security and add security tactics to their code with ease. We created a model that learns from existing open source projects and documentation using machine learning and text mining techniques. Our tool contains a module that runs in the background to analyze code as the programmer types and offers suggestions of where security could be included. In addition, our tool fetches existing open source implementations of cryptographic algorithms and sample code from repositories to aid programmers in adding security easily to their projects.