Characterization and modeling of top spam botnets

The increasing impact of the Internet in the global economy has transformed Botnets into one of the most relevant security threats for citizens, organizations and governments. Despite the significant efforts that have been made over the last years to understand this phenomenon and develop detection techniques and countermeasures, this continues to be a field with big challenges to address. Several approaches can be taken to study Botnets: analyze its source code, which can be a hard task because it is usually unavailable; study the control mechanism, particularly the activity of its Command and Control server(s); study its behavior, by measuring real traffic and collecting relevant statistics. In this work, we have installed some of the most popular spam Botnets, captured the originated traffic and characterized it in order to identify the main trends/patterns of their activity. From the intensive statistics that were collected, it was possible to conclude that there are distinct features between Botnets that can be explored to build efficient detection methodologies. Based on this study, the second part of the paper proposes a generic and systematic model to describe the network dynamics whenever a Botnet threat is detected, defining all actors, dimensions, states and actions that need to be taken into account at each moment. We believe that this type of modeling approach is the basis for developing systematic and integrated frameworks and strategies to predict and fight Botnet threats in an efficient way.This research was supported by Fundação para a Ciência e a Tecnologia, under research project PTDC/EEA-TEL/101880/2008

A structured approach to malware detection and analysis in digital forensics investigation

A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirement for the degree of PhDWithin the World Wide Web (WWW), malware is considered one of the most serious threats to system security with complex system issues caused by malware and spam. Networks and systems can be accessed and compromised by various types of malware, such as viruses, worms, Trojans, botnet and rootkits, which compromise systems through coordinated attacks. Malware often uses anti-forensic techniques to avoid detection and investigation. Moreover, the results of investigating such attacks are often ineffective and can create barriers for obtaining clear evidence due to the lack of sufficient tools and the immaturity of forensics methodology. This research addressed various complexities faced by investigators in the detection and analysis of malware. In this thesis, the author identified the need for a new approach towards malware detection that focuses on a robust framework, and proposed a solution based on an extensive literature review and market research analysis. The literature review focussed on the different trials and techniques in malware detection to identify the parameters for developing a solution design, while market research was carried out to understand the precise nature of the current problem. The author termed the new approaches and development of the new framework the triple-tier centralised online real-time environment (tri-CORE) malware analysis (TCMA). The tiers come from three distinctive phases of detection and analysis where the entire research pattern is divided into three different domains. The tiers are the malware acquisition function, detection and analysis, and the database operational function. This framework design will contribute to the field of computer forensics by making the investigative process more effective and efficient. By integrating a hybrid method for malware detection, associated limitations with both static and dynamic methods are eliminated. This aids forensics experts with carrying out quick, investigatory processes to detect the behaviour of the malware and its related elements. The proposed framework will help to ensure system confidentiality, integrity, availability and accountability. The current research also focussed on a prototype (artefact) that was developed in favour of a different approach in digital forensics and malware detection methods. As such, a new Toolkit was designed and implemented, which is based on a simple architectural structure and built from open source software that can help investigators develop the skills to critically respond to current cyber incidents and analyses

Fighting botnets - a systematic approach

The increasing impact of Internet in the global economy has transformed botnets into one of the most feared security threats for citizens, organizations and governments. Despite the significant efforts that have been made over the last years to understand this phenomenon and develop detection techniques and countermeasures, this continues to be a field with big challenges to address. The most important detection approaches and countermeasures that have been proposed are usually oriented to address some specific type of botnet threat or fight botnets in particular scenarios or conditions. This paper proposes a generic and systematic model to describe the network dynamics whenever a botnet threat is detected, defining all actors, dimensions, states and actions that need to be taken into account at each moment. We believe that the proposed model can be the basis for developing systematic and integrated frameworks, strategies and tools to predict and fight botnet threats in an efficient way.This research was supported by Fundação para a Ciência e a Tecnologia, under research project PTDC/EEA-TEL/101880/2008

Fast and Service-preserving Recovery from Malware Infections using CRIU

Once a computer system has been infected with malware, restoring it to an uninfected state often requires costly service-interrupting actions such as rolling back to a stable snapshot or reimaging the system entirely. We present CRIU-MR: a technique for restoring an infected server system running within a Linux container to an uninfected state in a service-preserving manner using Checkpoint/Restore in Userspace (CRIU). We modify the CRIU source code to flexibly integrate with existing malware detection technologies so that it can remove suspected malware processes within a Linux container during a checkpoint/restore event. This allows for infected containers with a potentially damaged filesystem to be checkpointed and subsequently restored on a fresh backup filesystem while both removing malware processes and preserving the state of trusted ones. This method can be quickly performed with minimal impact on service availability, restoring active TCP connections and completely removing several types of malware from infected Linux containers

Cyber Threat Intelligence Model: An Evaluation of Taxonomies, Sharing Standards, and Ontologies within Cyber Threat Intelligence

Cyber threat intelligence is the provision of evidence-based knowledge about existing or emerging threats. Benefits of threat intelligence include increased situational awareness and efficiency in security operations and improved prevention, detection, and response capabilities. To process, analyze, and correlate vast amounts of threat information and derive highly contextual intelligence that can be shared and consumed in meaningful times requires utilizing machine-understandable knowledge representation formats that embed the industry-required expressivity and are unambiguous. To a large extend, this is achieved by technologies like ontologies, interoperability schemas, and taxonomies. This research evaluates existing cyber-threat-intelligence-relevant ontologies, sharing standards, and taxonomies for the purpose of measuring their high-level conceptual expressivity with regards to the who, what, why, where, when, and how elements of an adversarial attack in addition to courses of action and technical indicators. The results confirmed that little emphasis has been given to developing a comprehensive cyber threat intelligence ontology with existing efforts not being thoroughly designed, non-interoperable and ambiguous, and lacking semantic reasoning capability

Improved Detection for Advanced Polymorphic Malware

Malicious Software (malware) attacks across the internet are increasing at an alarming rate. Cyber-attacks have become increasingly more sophisticated and targeted. These targeted attacks are aimed at compromising networks, stealing personal financial information and removing sensitive data or disrupting operations. Current malware detection approaches work well for previously known signatures. However, malware developers utilize techniques to mutate and change software properties (signatures) to avoid and evade detection. Polymorphic malware is practically undetectable with signature-based defensive technologies. Today’s effective detection rate for polymorphic malware detection ranges from 68.75% to 81.25%. New techniques are needed to improve malware detection rates. Improved detection of polymorphic malware can only be accomplished by extracting features beyond the signature realm. Targeted detection for polymorphic malware must rely upon extracting key features and characteristics for advanced analysis. Traditionally, malware researchers have relied on limited dimensional features such as behavior (dynamic) or source/execution code analysis (static). This study’s focus was to extract and evaluate a limited set of multidimensional topological data in order to improve detection for polymorphic malware. This study used multidimensional analysis (file properties, static and dynamic analysis) with machine learning algorithms to improve malware detection. This research demonstrated improved polymorphic malware detection can be achieved with machine learning. This study conducted a number of experiments using a standard experimental testing protocol. This study utilized three advanced algorithms (Metabagging (MB), Instance Based k-Means (IBk) and Deep Learning Multi-Layer Perceptron) with a limited set of multidimensional data. Experimental results delivered detection results above 99.43%. In addition, the experiments delivered near zero false positives. The study’s approach was based on single case experimental design, a well-accepted protocol for progressive testing. The study constructed a prototype to automate feature extraction, assemble files for analysis, and analyze results through multiple clustering algorithms. The study performed an evaluation of large malware sample datasets to understand effectiveness across a wide range of malware. The study developed an integrated framework which automated feature extraction for multidimensional analysis. The feature extraction framework consisted of four modules: 1) a pre-process module that extracts and generates topological features based on static analysis of machine code and file characteristics, 2) a behavioral analysis module that extracts behavioral characteristics based on file execution (dynamic analysis), 3) an input file construction and submission module, and 4) a machine learning module that employs various advanced algorithms. As with most studies, careful attention was paid to false positive and false negative rates which reduce their overall detection accuracy and effectiveness. This study provided a novel approach to expand the malware body of knowledge and improve the detection for polymorphic malware targeting Microsoft operating systems

Remedying Security Concerns at an Internet Scale

The state of security across the Internet is poor, and it has been so since the advent of the modern Internet. While the research community has made tremendous progress over the years in learning how to design and build secure computer systems, network protocols, and algorithms, we are far from a world where we can truly trust the security of deployed Internet systems. In reality, we may never reach such a world. Security concerns continue to be identified at scale through-out the software ecosystem, with thousands of vulnerabilities discovered each year. Meanwhile, attacks have become ever more frequent and consequential.As Internet systems will continue to be inevitably affected by newly found security concerns, the research community must develop more effective ways to remedy these issues. To that end, in this dissertation, we conduct extensive empirical measurements to understand how remediation occurs in practice for Internet systems, and explore methods for spurring improved remediation behavior. This dissertation provides a treatment of the complete remediation life cycle, investigating the creation, dissemination, and deployment of remedies. We start by focusing on security patches that address vulnerabilities, and analyze at scale their creation process, characteristics of the resulting fixes, and how these impact vulnerability remediation. We then investigate and systematize how administrators of Internet systems deploy software updates which patch vulnerabilities across the many machines they manage on behalf of organizations. Finally, we conduct the first systematic exploration of Internet-scale outreach efforts to disseminate information about security concerns and their remedies to system administrators, with an aim of driving their remediation decisions. Our results show that such outreach campaigns can effectively galvanize positive reactions.Improving remediation, particularly at scale, is challenging, as the problem space exhibits many dimensions beyond traditional computer technical considerations, including human, social, organizational, economic, and policy facets. To make meaningful progress, this work uses a diversity of empirical methods, from software data mining to user studies to Internet-wide network measurements, to systematically collect and evaluate large-scale datasets. Ultimately, this dissertation establishes broad empirical grounding on security remediation in practice today, as well as new approaches for improved remediation at an Internet scale

Resilience Strategies for Network Challenge Detection, Identification and Remediation

The enormous growth of the Internet and its use in everyday life make it an attractive target for malicious users. As the network becomes more complex and sophisticated it becomes more vulnerable to attack. There is a pressing need for the future internet to be resilient, manageable and secure. Our research is on distributed challenge detection and is part of the EU Resumenet Project (Resilience and Survivability for Future Networking: Framework, Mechanisms and Experimental Evaluation). It aims to make networks more resilient to a wide range of challenges including malicious attacks, misconfiguration, faults, and operational overloads. Resilience means the ability of the network to provide an acceptable level of service in the face of significant challenges; it is a superset of commonly used definitions for survivability, dependability, and fault tolerance. Our proposed resilience strategy could detect a challenge situation by identifying an occurrence and impact in real time, then initiating appropriate remedial action. Action is autonomously taken to continue operations as much as possible and to mitigate the damage, and allowing an acceptable level of service to be maintained. The contribution of our work is the ability to mitigate a challenge as early as possible and rapidly detect its root cause. Also our proposed multi-stage policy based challenge detection system identifies both the existing and unforeseen challenges. This has been studied and demonstrated with an unknown worm attack. Our multi stage approach reduces the computation complexity compared to the traditional single stage, where one particular managed object is responsible for all the functions. The approach we propose in this thesis has the flexibility, scalability, adaptability, reproducibility and extensibility needed to assist in the identification and remediation of many future network challenges

GUIDE FOR THE COLLECTION OF INSTRUSION DATA FOR MALWARE ANALYSIS AND DETECTION IN THE BUILD AND DEPLOYMENT PHASE

During the COVID-19 pandemic, when most businesses were not equipped for remote work and cloud computing, we saw a significant surge in ransomware attacks. This study aims to utilize machine learning and artificial intelligence to prevent known and unknown malware threats from being exploited by threat actors when developers build and deploy applications to the cloud. This study demonstrated an experimental quantitative research design using Aqua. The experiment\u27s sample is a Docker image. Aqua checked the Docker image for malware, sensitive data, Critical/High vulnerabilities, misconfiguration, and OSS license. The data collection approach is experimental. Our analysis of the experiment demonstrated how unapproved images were prevented from running anywhere in our environment based on known vulnerabilities, embedded secrets, OSS licensing, dynamic threat analysis, and secure image configuration. In addition to the experiment, the forensic data collected in the build and deployment phase are exploitable vulnerability, Critical/High Vulnerability Score, Misconfiguration, Sensitive Data, and Root User (Super User). Since Aqua generates a detailed audit record for every event during risk assessment and runtime, we viewed two events on the Audit page for our experiment. One of the events caused an alert due to two failed controls (Vulnerability Score, Super User), and the other was a successful event meaning that the image is secure to deploy in the production environment. The primary finding for our study is the forensic data associated with the two events on the Audit page in Aqua. In addition, Aqua validated our security controls and runtime policies based on the forensic data with both events on the Audit page. Finally, the study’s conclusions will mitigate the likelihood that organizations will fall victim to ransomware by mitigating and preventing the total damage caused by a malware attack

Robust and secure monitoring and attribution of malicious behaviors

Worldwide computer systems continue to execute malicious software that degrades the systemsâ performance and consumes network capacity by generating high volumes of unwanted traffic. Network-based detectors can effectively identify machines participating in the ongoing attacks by monitoring the traffic to and from the systems. But, network detection alone is not enough; it does not improve the operation of the Internet or the health of other machines connected to the network. We must identify malicious code running on infected systems, participating in global attack networks. This dissertation describes a robust and secure approach that identifies malware present on infected systems based on its undesirable use of network. Our approach, using virtualization, attributes malicious traffic to host-level processes responsible for the traffic. The attribution identifies on-host processes, but malware instances often exhibit parasitic behaviors to subvert the execution of benign processes. We then augment the attribution software with a host-level monitor that detects parasitic behaviors occurring at the user- and kernel-level. User-level parasitic attack detection happens via the system-call interface because it is a non-bypassable interface for user-level processes. Due to the unavailability of one such interface inside the kernel for drivers, we create a new driver monitoring interface inside the kernel to detect parasitic attacks occurring through this interface. Our attribution software relies on a guest kernelâ s data to identify on-host processes. To allow secure attribution, we prevent illegal modifications of critical kernel data from kernel-level malware. Together, our contributions produce a unified research outcome --an improved malicious code identification system for user- and kernel-level malware.Ph.D.Committee Chair: Giffin, Jonathon; Committee Member: Ahamad, Mustaque; Committee Member: Blough, Douglas; Committee Member: Lee, Wenke; Committee Member: Traynor, Patric