Approaches and Techniques for Fingerprinting and Attributing Probing Activities by Observing Network Telescopes

The explosive growth, complexity, adoption and dynamism of cyberspace over the last decade has radically altered the globe. A plethora of nations have been at the very forefront of this change, fully embracing the opportunities provided by the advancements in science and technology in order to fortify the economy and to increase the productivity of everyday's life. However, the significant dependence on cyberspace has indeed brought new risks that often compromise, exploit and damage invaluable data and systems. Thus, the capability to proactively infer malicious activities is of paramount importance. In this context, generating cyber threat intelligence related to probing or scanning activities render an effective tactic to achieve the latter. In this thesis, we investigate such malicious activities, which are typically the precursors of various amplified, debilitating and disrupting cyber attacks. To achieve this task, we analyze real Internet-scale traffic targeting network telescopes or darknets, which are defined by routable, allocated yet unused Internet Protocol addresses. First, we present a comprehensive survey of the entire probing topic. Specifically, we categorize this topic by elaborating on the nature, strategies and approaches of such probing activities. Additionally, we provide the reader with a classification and an exhaustive review of various techniques that could be employed in such malicious activities. Finally, we depict a taxonomy of the current literature by focusing on distributed probing detection methods. Second, we focus on the problem of fingerprinting probing activities. To this end, we design, develop and validate approaches that can identify such activities targeting enterprise networks as well as those targeting the Internet-space. On one hand, the corporate probing detection approach uniquely exploits the information that could be leaked to the scanner, inferred from the internal network topology, to perform the detection. On the other hand, the more darknet tailored probing fingerprinting approach adopts a statistical approach to not only detect the probing activities but also identify the exact technique that was employed in the such activities. Third, for attribution purposes, we propose a correlation approach that fuses probing activities with malware samples. The approach aims at detecting whether Internet-scale machines are infected or not as well as pinpointing the exact malware type/family, if the machines were found to be compromised. To achieve the intended goals, the proposed approach initially devises a probabilistic model to filter out darknet misconfiguration traffic. Consequently, probing activities are correlated with malware samples by leveraging fuzzy hashing and entropy based techniques. To this end, we also investigate and report a rare Internet-scale probing event by proposing a multifaceted approach that correlates darknet, malware and passive dns traffic. Fourth, we focus on the problem of identifying and attributing large-scale probing campaigns, which render a new era of probing events. These are distinguished from previous probing incidents as (1) the population of the participating bots is several orders of magnitude larger, (2) the target scope is generally the entire Internet Protocol (IP) address space, and (3) the bots adopt well-orchestrated, often botmaster coordinated, stealth scan strategies that maximize targets' coverage while minimizing redundancy and overlap. To this end, we propose and validate three approaches. On one hand, two of the approaches rely on a set of behavioral analytics that aim at scrutinizing the generated traffic by the probing sources. Subsequently, they employ data mining and graph theoretic techniques to systematically cluster the probing sources into well-defined campaigns possessing similar behavioral similarity. The third approach, on the other hand, exploit time series interpolation and prediction to pinpoint orchestrated probing campaigns and to filter out non-coordinated probing flows. We conclude this thesis by highlighting some research gaps that pave the way for future work

Monitoring Network Telescopes and Inferring Anomalous Traffic Through the Prediction of Probing Rates

International audienceNetwork reconnaissance is the first step precedinga cyber-attack. Hence, monitoring the probing activities is im-perative to help security practitioners enhancing their awarenessabout Internet’s large-scale events or peculiar events targetingtheir network. In this paper, we present a framework foran improved and efficient monitoring of the probing activi-ties targeting network telescopes. Particularly, we model theprobing rates which are a good indicator for measuring thecyber-security risk targeting network services. The approachconsists of first inferring groups of network ports sharing similarprobing characteristics through a new affinity metric capturingboth temporal and semantic similarities between ports. Then,sequences of probing rates targeting similar ports are used asinputs to stacked Long Short-Term Memory (LSTM) neuralnetworks to predict probing rates 1 hour and 1 day in advance.Finally, we describe two monitoring indicators that use theprediction models to infer anomalous probing traffic and toraise early threat warnings. We show that LSTM networkscan accurately predict probing rates, outperforming the non-stationary autoregressive model, and we demonstrate that themonitoring indicators are efficient in assessing the cyber-securityrisk related to vulnerability disclosur

Data-Driven Approaches for Detecting Malware-Infected IoT Devices and Characterizing Their Unsolicited Behaviors by Leveraging Passive Internet Measurements

Despite the benefits of Internet of Things (IoT) devices, the insecurity of IoT and their deployment nature have turned them into attractive targets for adversaries, which contributed to the rise of IoT-tailored malware as a major threat to the Internet ecosystem. In this thesis, we address the threats associated with the emerging IoT malware, which utilize exploited devices to perform large-scale cyber attacks (e.g., DDoS). To mitigate such threat, there is a need to possess an Internet perspective of the deployed IoT devices while building a better understanding about the behavioral characteristic of malware-infected devices, which is challenging due to the lack of empirical data and knowledge about the deployed IoT devices and their behavioral characteristics. To address these challenges, in this thesis, we leverage passive Internet measurements and IoT device information to detect exploited IoT devices and investigate their generated traffic at the network telescope (darknet). We aim at proposing data-driven approaches for effective and near real-time IoT threat detection and characterization. Additionally, we leverage a specialized IoT Honeypot to analyze a large corpus of real IoT malware binary executable. We aim at building a better understanding about the current state of IoT malware while addressing the problems of IoT malware classification and family attribution. To this end, we perform the following to achieve our objectives: First, we address the lack of empirical data and knowledge about IoT devices and their activities. To this end, we leverage an online IoT search engine (e.g., Shodan.io) to obtain publicly available device information in the realms of consumer and cyber-physical system (CPS), while utilizing passive network measurements collected at a large-scale network telescope (CAIDA), to infer compromised devices and their unsolicited activities. Indeed, we were among the first to report experimental results on detecting compromised IoT devices and their behavioral characteristics in the wild, while demonstrating their active involvement in large-scale malware-generated malicious activities such as Internet scanning. Additionally, we leverage the IoT-generated backscatter traffic towards the network telescope to shed light on IoT devices that were victims of intensive Denial of Service (DoS) attacks. Second, given the highly orchestrated nature of IoT-driven cyber-attacks, we focus on the analysis of IoT-generated scanning activities to detect and characterize scanning campaigns generated by IoT botnets. To this end, we aggregate IoT-generated traffic and performing association rules mining to infer campaigns through common scanning objectives represented by targeted destination ports. Further, we leverage behavioural characteristics and aggregated flow features to correlate IoT devices using DBSCAN clustering algorithm. Indeed, our findings shed light on compromised IoT devices, which tend to operate within well coordinated IoT botnets. Third, considering the huge number of IoT devices and the magnitude of their malicious scanning traffic, we focus on addressing the operational challenges to automate large-scale campaign detection and analysis while generating threat intelligence in a timely manner. To this end, we leverage big data analytic frameworks such as Apache Spark to develop a scalable system for automated detection of infected IoT devices and characterization of their scanning activities using our proposed approach. Our evaluation results with over 4TB of IoT traffic demonstrated the effectiveness of the system to infer scanning campaigns generated by IoT botnets. Moreover, we demonstrate the feasibility of the implemented system/framework as a platform for implementing further supporting applications, which leverage passive Internet measurement for characterizing IoT traffic and generating IoT-related threat intelligence. Fourth, we take first steps towards mitigating threats associated with the rise of IoT malware by creating a better understanding about the characteristics and inter-relations of IoT malware. To this end, we analyze about 70,000 IoT malware binaries obtained by a specialized IoT honeypot in the past two years. We investigate the distribution of IoT malware across known families, while exploring their detection timeline and persistent. Moreover, while we shed light on the effectiveness of IoT honeypots in detecting new/unknown malware samples, we utilize static and dynamic malware analysis techniques to uncover adversarial infrastructure and investigate functional similarities. Indeed, our findings enable unknown malware labeling/attribution while identifying new IoT malware variants. Additionally, we collect malware-generated scanning traffic (whenever available) to explore behavioral characteristics and associated threats/vulnerabilities. We conclude this thesis by discussing research gaps that pave the way for future work

Behavioral Service Graphs: A Big Data Approach for Prompt Investigation of Internet-Wide Infections

The 8th IFIP International Conference on New Technologies, Mobility and Security (NTMS 2016), Larnaca, Cyprus, 21-23 November 2016The task of generating network-based evidence to support network forensic investigation is becoming increasingly prominent. Undoubtedly, such evidence is significantly imperative as it not only can be used to diagnose and respond to various network-related issues (i.e., performance bottlenecks, routing issues, etc.) but more importantly, can be leveraged to infer and further investigate network security intrusions and infections. In this context, this paper proposes a proactive approach that aims at generating accurate and actionable network-based evidence related to groups of compromised network machines. The approach is envisioned to guide investigators to promptly pinpoint such malicious groups for possible immediate mitigation as well as empowering network and digital forensic specialists to further examine those machines using auxiliary collected data or extracted digital artifacts. On one hand, the promptness of the approach is successfully achieved by monitoring and correlating perceived probing activities, which are typically the very first signs of an infection or misdemeanors. On the other hand, the generated evidence is accurate as it is based on an anomaly inference that fuses big data behavioral analytics in conjunction with formal graph theoretical concepts. We evaluate the proposed approach as a global capability in a security operations center. The empirical evaluations, which employ 80 GB of real darknet traffic, indeed demonstrates the accuracy, effectiveness and simplicity of the generated network-based evidence

On Leveraging Next-Generation Deep Learning Techniques for IoT Malware Classification, Family Attribution and Lineage Analysis

Recent years have witnessed the emergence of new and more sophisticated malware targeting insecure Internet of Things (IoT) devices, as part of orchestrated large-scale botnets. Moreover, the public release of the source code of popular malware families such as Mirai [1] has spawned diverse variants, making it harder to disambiguate their ownership, lineage, and correct label. Such a rapidly evolving landscape makes it also harder to deploy and generalize effective learning models against retired, updated, and/or new threat campaigns. To mitigate such threat, there is an utmost need for effective IoT malware detection, classification and family attribution, which provide essential steps towards initiating attack mitigation/prevention countermeasures, as well as understanding the evolutionary trajectories and tangled relationships of IoT malware. This is particularly challenging due to the lack of fine-grained empirical data about IoT malware, the diverse architectures of IoT-targeted devices, and the massive code reuse between IoT malware families. To address these challenges, in this thesis, we leverage the general lack of obfuscation in IoT malware to extract and combine static features from multi-modal views of the executable binaries (e.g., images, strings, assembly instructions), along with Deep Learning (DL) architectures for effective IoT malware classification and family attribution. Additionally, we aim to address concept drift and the limitations of inter-family classification due to the evolutionary nature of IoT malware, by detecting in-class evolving IoT malware variants and interpreting the meaning behind their mutations. To this end, we perform the following to achieve our objectives: First, we analyze 70,000 IoT malware samples collected by a specialized IoT honeypot and popular malware repositories in the past 3 years. Consequently, we utilize features extracted from strings- and image-based representations of IoT malware to implement a multi-level DL architecture that fuses the learned features from each sub-component (i.e, images, strings) through a neural network classifier. Our in-depth experiments with four prominent IoT malware families highlight the significant accuracy of the proposed approach (99.78%), which outperforms conventional single-level classifiers, by relying on different representations of the target IoT malware binaries that do not require expensive feature extraction. Additionally, we utilize our IoT-tailored approach for labeling unknown malware samples, while identifying new malware strains. Second, we seek to identify when the classifier shows signs of aging, by which it fails to effectively recognize new variants and adapt to potential changes in the data. Thus, we introduce a robust and effective method that uses contrastive learning and attentive Transformer models to learn and compare semantically meaningful representations of IoT malware binaries and codes without the need for expensive target labels. We find that the evolution of IoT binaries can be used as an augmentation strategy to learn effective representations to contrast (dis)similar variant pairs. We discuss the impact and findings of our analysis and present several evaluation studies to highlight the tangled relationships of IoT malware, as well as the efficiency of our contrastively learned fine-grained feature vectors in preserving semantics and reducing out-of-vocabulary size in cross-architecture IoT malware binaries. We conclude this thesis by summarizing our findings and discussing research gaps that lay the way for future work

Measuring for privacy: From tracking to cloaking

We rely on various types of online services to access information for different uses, and often provide sensitive information during the interactions with these services. These online services are of different types; e.g. commercial websites (e.g., banking, education, news, shopping, dating, social media), essential websites (e.g., government). Online services are available through websites as well as mobile apps. The growth of web sites, mobile devices and apps that run on those devices, have resulted in the proliferation of online services. This whole ecosystem of online services had created an environment where everyone using it are being tracked. Several past studies have performed privacy measurements to assess the prevalence of tracking in online services. Most of these studies used institutional (i.e., non-residential) resources for their measurements, and lacked global perspective. Tracking on online services and its impact to privacy may differ at various locations. Therefore, to fill in this gap, we perform a privacy measurement study of popular commercial websites, using residential networks from various locations. Unlike commercial online services, there are different categories (e.g., government, hospital, religion) of essential online services where users do not expect to be tracked. The users of these essential online services often use information of extreme personal and sensitive in nature (e.g., social insurance number, health information, prayer requests/confessions made to a religious minister) when interacting with those services. However, contrary to the expectations of users, these essential services include user tracking capabilities. We built frameworks to perform privacy measurements of these online services (include both web sites and Android apps) that are of different types (i.e., governments, hospitals and religious services in jurisdictions around the world). The instrumented tracking metrics (i.e., stateless, stateful, session replaying) from the privacy measurements of these online services are then analyzed. Malicious sites (e.g., phishing) mimic online services to deceive users, causing them harm. We found 80% of analyzed malicious sites are cloaked, and not blocked by search engine crawlers. Therefore, sensitive information collected from users through these sites is exposed. In addition, underlying Internet-connected infrastructure (e.g., networked devices such as routers, modems) used by online users, can suffer from security issues due to nonuse of TLS or use of weak SSL/TLS certificates. Such security issues (e.g., spying on a CCTV camera) can compromise data integrity, confidentiality and user privacy. Overall, we found tracking on commercial websites differ based on the location of corresponding residential users. We also observed widespread use of tracking by commercial trackers, and session replay services that expose sensitive information from essential online services. Sensitive information are also exposed due to vulnerabilities in online services (e.g., Cross Site Scripting). Furthermore, a significant proportion of malicious sites evade detection by security/search engine crawlers, which may make such sites readily available to users. We also detect weaknesses in the TLS ecosystem of Internet-connected infrastructure that supports running these online services. These observations require more research on privacy of online services, as well as information exposure from malicious online services, to understand the significance of privacy issues, and to adopt appropriate mitigation strategies

The entangled cyberspace: an integrated approach for predicting cyber-attacks

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonSignificant studies in cyber defence analysis have predominantly revolved around a single linear analysis of information from a single source of evidence (The Network). These studies were limited in their ability to understand the dynamics of entanglements related to cyber-incidents. This research integrates evidence beyond the network in an attempt to understand and predict phases of the kill-chain across the information space. This research provides a multi-dimensional phased analysis of the traditional kill-chain model using structural vector autoregressive models. In the ‘Entangled Cyberspace Framework’, each phase of the kill-chain corresponds to a single dimension of the information space based on time observations of certain events. Events are represented as time signals, where each phase is characterised by multiple time signals representing multiple events on that phase. Multiple time signals are analysed using structural models for multiple time series analysis (Vector Auto-Regressive models). At each phase of the kill-chain, we perform a lagged co-integration analysis of events across the information space. This nature of analysis detects hidden entanglements that characterise events in the kill-chain beyond the network. The measured prediction accuracy and error measured at each stage of the experiment represents the usefulness of selected events in characterising the defined stage of the kill-chain. The entangled cyberspace, in theory, is the fusion of three conceptual foundations: a) A multi-dimensional characterisation of cyberspace, b) A sequential phased model for perpetrating cyber-attacks and c) A structural model for integrating and simultaneously analysing multiple sources of evidence. It starts with the characterisation of the information space into different dimensions of interest. The framework goes further to identify evidence sources across these characterised dimensions and integrates them in the analytical context under consideration (e.g. Malware Injection). The concrete findings show that our approach and analytical methodology are capable of detecting entanglements when applied to a set of entangled activities across the information space. The findings also prove that activities beyond the network have significant effects on the nature of the unfolding cyber-attack vector. The predictive features of events across the kill-chain were also presented in this research as opinion and emotion drivers on the social dimension, packet data details and social and cultural events on the economic layer. Finally, co-integration detected between events across and within dimensions of the information space proves the existence of both inter-dimensional and intra-dimensional entanglements that affect the nature of events unfolding during the kill-chain (from the adversary’s point of view). The novelty of this research rests in the ability to hop across the information space for detecting evidential clues of activities that are related-to cyber-incidents. This research also expands the standard multi-dimensional information space to include SPEC factors as indicators of cyber-incidents. This research improves the current information security management model, specifically in the monitoring, analysis and detection phases. This research provides a methodology that accommodates a robust evidence base for understanding the attack surface. Practically, this research provides a basis for creating applications and tools for protecting critical national infrastructure by integrating data from social platforms, real-world political, cultural and economic events and the cyber-physical

Organizational Behavior

Organizational Behavior bridges the gap between theory and practice with a distinct experiential approach. On average, a worker in the USA will change jobs 10 times in 20 years. In order to succeed in this type of career situation, individuals need to be armed with the tools necessary to be life-long learners. To that end, this book is not be about giving students all the answers to every situation they may encounter when they start their first job or as they continue up the career ladder. Instead, this book gives students the vocabulary, framework, and critical thinking skills necessary to diagnose situations, ask tough questions, evaluate the answers received, and to act in an effective and ethical manner regardless of situational characteristics. Often, students taking OB either do not understand how important knowledge of OB can be to their professional careers, or they DO understand and they want to put that knowledge into practice. Organizational Behavior takes a more experiential angle to the material to meet both of those needs. The experiential approach can be incorporated in the classroom primarily through the OB Toolbox. This feature brings life to the concepts and allows students to not only see how the OB theories unfold, but to practice them, as well