Modern malware can take various forms, and has reached a very high level of sophistication in terms of its penetration, persistence, communication and hiding capabilities. The use of cryptography, and of covert communication channels over public and widely used protocols and services, is becoming a norm. In this work, we start by introducing Resource Identifier Generation Algorithms. These are an extension of a well-known mechanism called Domain Generation Algorithms, which are frequently employed by cybercriminals for bot management and communication. Our extension allows, beyond DNS, the use of other protocols. More concretely, we showcase the exploitation of the InterPlanetary file system (IPFS). This is a solution for the "permanent web", which enjoys a steadily growing community interest and adoption. The IPFS is, in addition, one of the most prominent solutions for blockchain storage. We go beyond the straightforward case of using the IPFS for hosting malicious content, and explore ways in which a botmaster could employ it, to manage her bots, validating our findings experimentally. Finally, we discuss the advantages of our approach for malware authors, its efficacy and highlight its extensibility for other distributed storage services.
Nowadays, most malware-based campaigns rely on the use of botnets, commanded by remote servers (i.e. C &C servers), which send instructions orders to infected devices @cite_31 . In the past, the mechanism used to find such C &C servers was to hardcode IP addresses in the malware. However, such technique entailed a set of drawbacks for the attackers @cite_0 (e.g. easy to take-down). Therefore, botnets evolved into peer-to-peer (P2P) botnets @cite_35 , which adopted a myriad of techniques such as the approach, which imitates content distribution networks by resolving a domain name to multiple IP addresses @cite_38 @cite_4 .
@cite_35 @cite_38 @cite_4 @cite_0 @cite_31
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Botnets have recently been identified as one of the most important threats to the security of the Internet. Traditionally, botnets organize themselves in an hierarchical manner with a central command and control location. This location can be statically defined in the bot, or it can be dynamically defined based on a directory server. Presently, the centralized characteristic of botnets is useful to security professionals because it offers a central point of failure for the botnet. In the near future, we believe attackers will move to more resilient architectures. In particular, one class of botnet structure that has entered initial stages of development is peer-to-peer based architectures. In this paper, we present an overview of peer-to-peer botnets. We also present a case study of a Kademlia-based Trojan.Peacomm bot. We present the first empirical study of fast-flux service networks (FFSNs), a newly emerging and still not widelyknown phenomenon in the Internet. FFSNs employ DNS to establish a proxy network on compromised machines through which illegal online services can be hosted with very high availability. Through our measurements we show that the threat which FFSNs pose is significant: FFSNs occur on a worldwide scale and already host a substantial percentage of online scams. Based on analysis of the principles of FFSNs, we develop a metric with which FFSNs can be effectively detected. Considering our detection technique we also discuss possible mitigation strategies. Devices infected with malicious software typically form botnet armies under the influence of one or more command and control (C&C) servers. The botnet problem reached such levels where federal law enforcement agencies have to step in and take actions against botnets by disrupting (or “taking down”) their C&Cs, and thus their illicit operations. Lately, more and more private companies have started to independently take action against botnet armies, primarily focusing on their DNS-based C&Cs. While well-intentioned, their C&C takedown methodology is in most cases ad-hoc, and limited by the breadth of knowledge available around the malware that facilitates the botnet. With this paper, we aim to bring order, measure, and reason to the botnet takedown problem. We improve an existing takedown analysis system called rza . Specifically, we examine additional botnet takedowns, enhance the risk calculation to use botnet population counts, and include a detailed discussion of policy improvements that can be made to improve takedowns. As part of our system evaluation, we perform a postmortem analysis of the recent 3322.org, Citadel, and No-IP takedowns. The Mirai botnet, composed primarily of embedded and IoT devices, took the Internet by storm in late 2016 when it overwhelmed several high-profile targets with massive distributed denial-of-service (DDoS) attacks. In this paper, we provide a seven-month retrospective analysis of Mirai's growth to a peak of 600k infections and a history of its DDoS victims. By combining a variety of measurement perspectives, we analyze how the botnet emerged, what classes of devices were affected, and how Mirai variants evolved and competed for vulnerable hosts. Our measurements serve as a lens into the fragile ecosystem of IoT devices. We argue that Mirai may represent a sea change in the evolutionary development of botnets--the simplicity through which devices were infected and its precipitous growth, demonstrate that novice malicious techniques can compromise enough low-end devices to threaten even some of the best-defended targets. To address this risk, we recommend technical and nontechnical interventions, as well as propose future research directions.