Packet analysis for network forensics: A comprehensive survey

Packet analysis is a primary traceback technique in network forensics, which, providing that the packet details captured are sufficiently detailed, can play back even the entire network traffic for a particular point in time. This can be used to find traces of nefarious online behavior, data breaches, unauthorized website access, malware infection, and intrusion attempts, and to reconstruct image files, documents, email attachments, etc. sent over the network. This paper is a comprehensive survey of the utilization of packet analysis, including deep packet inspection, in network forensics, and provides a review of AI-powered packet analysis methods with advanced network traffic classification and pattern identification capabilities. Considering that not all network information can be used in court, the types of digital evidence that might be admissible are detailed. The properties of both hardware appliances and packet analyzer software are reviewed from the perspective of their potential use in network forensics

Study of Peer-to-Peer Network Based Cybercrime Investigation: Application on Botnet Technologies

The scalable, low overhead attributes of Peer-to-Peer (P2P) Internet protocols and networks lend themselves well to being exploited by criminals to execute a large range of cybercrimes. The types of crimes aided by P2P technology include copyright infringement, sharing of illicit images of children, fraud, hacking/cracking, denial of service attacks and virus/malware propagation through the use of a variety of worms, botnets, malware, viruses and P2P file sharing. This project is focused on study of active P2P nodes along with the analysis of the undocumented communication methods employed in many of these large unstructured networks. This is achieved through the design and implementation of an efficient P2P monitoring and crawling toolset. The requirement for investigating P2P based systems is not limited to the more obvious cybercrimes listed above, as many legitimate P2P based applications may also be pertinent to a digital forensic investigation, e.g, voice over IP, instant messaging, etc. Investigating these networks has become increasingly difficult due to the broad range of network topologies and the ever increasing and evolving range of P2P based applications. In this work we introduce the Universal P2P Network Investigation Framework (UP2PNIF), a framework which enables significantly faster and less labour intensive investigation of newly discovered P2P networks through the exploitation of the commonalities in P2P network functionality. In combination with a reference database of known network characteristics, it is envisioned that any known P2P network can be instantly investigated using the framework, which can intelligently determine the best investigation methodology and greatly expedite the evidence gathering process. A proof of concept tool was developed for conducting investigations on the BitTorrent network.Comment: This is a thesis submitted in fulfilment of a PhD in Digital Forensics and Cybercrime Investigation in the School of Computer Science, University College Dublin in October 201

INFERENCE-BASED FORENSICS FOR EXTRACTING INFORMATION FROM DIVERSE SOURCES

Digital forensics is tasked with the examination and extraction of evidence from a diverse set of devices and information sources. While digital forensics has long been synonymous with file recovery, this label no longer adequately describes the science’s role in modern investigations. Spurred by evolving technologies and online crime, law enforcement is shifting the focus of digital forensics from its traditional role in the final stages of an investigation to assisting investigators in the earliest phases — often before a suspect has been identified and a warrant served. Investigators need new forensic techniques to investigate online crimes, such as child pornography trafficking on peer-to-peer networks (p2p), and to extract evidence from new information sources, such as mobile phones. The traditional approach of developing tools tailored specifically to each source is no longer tenable given the diversity, volume of storage, and introduction rate of new devices and network applications. Instead, we propose the adoption of flexible, inference-based techniques to extract evidence from any format. Such techniques can be readily applied to a wide variety of different evidence sources without requiring significant manual work on the investigator’s part. The primary contribution of my dissertation is a set of novel forensic techniques for extracting information from diverse data sources. We frame the evaluation using two different, but increasingly important, forensic scenarios: mobile phone triage and network-based investigations. Via probabilistic descriptions of typical data structures, and using a classic dynamic programming algorithm, our phone triage techniques are able to identify user information in phones across varied models and manufacturers. We also show how to incorporate feedback from the investigator to improve the usability of extracted information. For network-based investigations, we quantify and characterize the extent of contraband trafficking on peer-to-peer networks. We suggest various techniques for prioritizing law enforcement’s limited resources. We finally investigate techniques that use system logs to generate and then analyze a finite state model of a protocol’s implementation. The objective is to infer behavior that an investigator can leverage to further law enforcement objectives. We evaluate all of our techniques using the real-world legal constraints and restrictions of investigators

Understanding the Usage of Anonymous Onion Services: Empirical Experiments to Study Criminal Activities in the Tor Network

Technology is the new host of life, and with each passing year, developments in digitalization make it easier to destroy our understanding of authenticity. A man is more than his distorted shadow on Facebook wall. Another essential shadow dwells under anonymity.The aim of this thesis is to understand the usage of onion services in the Tor anonymity network. To be more precise the aim is to discover and measure human activities on Tor and on anonymous onion websites. We establish novel facts in the anonymous online environment. We solve technical problems, such as web-crawling and scraping to gather data. We represent new findings on how onion services hide illegal activities. The results are merged with wider range of anonymous onion services usage.We selected to cast light to the criminal dark side of the Tor network, mainly black marketplaces and hacking. This is a somewhat factitious selection from the wide range of Tor use. However, an archetype villain is found in nearly every story so naturally, for the sake of being interesting, we selected criminal phenomenon to study. To be clear, the Tor network is developed and utilised for legal online privacy and several other essential ways.The first finding is that as the Tor network becomes more popular also illegal activities become wide spread. Tor and virtual currencies are already transforming drug trade. Anonymous high-class marketplaces are difficult for the law enforcement to interrupt.On the other hand, now illegal activities are paradoxically more public than ever: everyone can access these onion sites and browse the product listings. The illegal trade is transparent to be followed. For example, by the means of web-crawling and scraping, we produced nearly real-time picture of the trade in Finland following one of the marketplaces on Tor. As a result, statistics shed light on substance consumption habits: the second study estimates that sales totalled over two million euros between Finnish buyers and sellers.Due to the network’s anonymity and nature of illegal sales, reputation systems have replaced the rule of law: a buyer trusts the seller’s reputation because the law is not guaranteeing the delivery. The only available information is the seller’s reputation and capacity which were both associated with drug sales as we prove.Finally, we will identify the limits of online anonymity ranging from technical limitations to operation security dangers. Technology is merely a communication channel and major criminal activities still happen in the physical world. For instance, a drug trade requires that the seller sends the products using post service to the buyer’s address. Before that the seller has acquired enormous amounts of illegal drugs. The buyer has to give away his address to the seller who could later be placed under arrest with a list of customers addresses. Furthermore, we show case by case how criminals reveal and leak their critical identity information. The law enforcement agencies are experienced to investigate all of these aspects even if the Tor network itself is secure

Tracking and Mitigation of Malicious Remote Control Networks

Attacks against end-users are one of the negative side effects of today’s networks. The goal of the attacker is to compromise the victim’s machine and obtain control over it. This machine is then used to carry out denial-of-service attacks, to send out spam mails, or for other nefarious purposes. From an attacker’s point of view, this kind of attack is even more efficient if she manages to compromise a large number of machines in parallel. In order to control all these machines, she establishes a "malicious remote control network", i.e., a mechanism that enables an attacker the control over a large number of compromised machines for illicit activities. The most common type of these networks observed so far are so called "botnets". Since these networks are one of the main factors behind current abuses on the Internet, we need to find novel approaches to stop them in an automated and efficient way. In this thesis we focus on this open problem and propose a general root cause methodology to stop malicious remote control networks. The basic idea of our method consists of three steps. In the first step, we use "honeypots" to collect information. A honeypot is an information system resource whose value lies in unauthorized or illicit use of that resource. This technique enables us to study current attacks on the Internet and we can for example capture samples of autonomous spreading malware ("malicious software") in an automated way. We analyze the collected data to extract information about the remote control mechanism in an automated fashion. For example, we utilize an automated binary analysis tool to find the Command & Control (C&C) server that is used to send commands to the infected machines. In the second step, we use the extracted information to infiltrate the malicious remote control networks. This can for example be implemented by impersonating as a bot and infiltrating the remote control channel. Finally, in the third step we use the information collected during the infiltration phase to mitigate the network, e.g., by shutting down the remote control channel such that the attacker cannot send commands to the compromised machines. In this thesis we show the practical feasibility of this method. We examine different kinds of malicious remote control networks and discuss how we can track all of them in an automated way. As a first example, we study botnets that use a central C&C server: We illustrate how the three steps can be implemented in practice and present empirical measurement results obtained on the Internet. Second, we investigate botnets that use a peer-to-peer based communication channel. Mitigating these botnets is harder since no central C&C server exists which could be taken offline. Nevertheless, our methodology can also be applied to this kind of networks and we present empirical measurement results substantiating our method. Third, we study fast-flux service networks. The idea behind these networks is that the attacker does not directly abuse the compromised machines, but uses them to establish a proxy network on top of these machines to enable a robust hosting infrastructure. Our method can be applied to this novel kind of malicious remote control networks and we present empirical results supporting this claim. We anticipate that the methodology proposed in this thesis can also be used to track and mitigate other kinds of malicious remote control networks

The Proceedings of 15th Australian Information Security Management Conference, 5-6 December, 2017, Edith Cowan University, Perth, Australia

Conference Foreword The annual Security Congress, run by the Security Research Institute at Edith Cowan University, includes the Australian Information Security and Management Conference. Now in its fifteenth year, the conference remains popular for its diverse content and mixture of technical research and discussion papers. The area of information security and management continues to be varied, as is reflected by the wide variety of subject matter covered by the papers this year. The papers cover topics from vulnerabilities in “Internet of Things” protocols through to improvements in biometric identification algorithms and surveillance camera weaknesses. The conference has drawn interest and papers from within Australia and internationally. All submitted papers were subject to a double blind peer review process. Twenty two papers were submitted from Australia and overseas, of which eighteen were accepted for final presentation and publication. We wish to thank the reviewers for kindly volunteering their time and expertise in support of this event. We would also like to thank the conference committee who have organised yet another successful congress. Events such as this are impossible without the tireless efforts of such people in reviewing and editing the conference papers, and assisting with the planning, organisation and execution of the conference. To our sponsors, also a vote of thanks for both the financial and moral support provided to the conference. Finally, thank you to the administrative and technical staff, and students of the ECU Security Research Institute for their contributions to the running of the conference

Code: Version 2.0

Discusses the regulation of cyberspace via code, as well as possible trends to expect in this regulation. Additional topics discussed in this context include intellectual property, privacy, and free speech