Visible to the public Biblio

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2022-01-10
Stan, Orly, Bitton, Ron, Ezrets, Michal, Dadon, Moran, Inokuchi, Masaki, Ohta, Yoshinobu, Yagyu, Tomohiko, Elovici, Yuval, Shabtai, Asaf.  2021.  Heuristic Approach for Countermeasure Selection Using Attack Graphs. 2021 IEEE 34th Computer Security Foundations Symposium (CSF). :1–16.
Selecting the optimal set of countermeasures to secure a network is a challenging task, since it involves various considerations and trade-offs, such as prioritizing the risks to mitigate given the mitigation costs. Previously suggested approaches are based on limited and largely manual risk assessment procedures, provide recommendations for a specific event, or don't consider the organization's constraints (e.g., limited budget). In this paper, we present an improved attack graph-based risk assessment process and apply heuristic search to select an optimal countermeasure plan for a given network and budget. The risk assessment process represents the risk in the system in such a way that incorporates the quantitative risk factors and relevant countermeasures; this allows us to assess the risk in the system under different countermeasure plans during the search, without the need to regenerate the attack graph. We also provide a detailed description of countermeasure modeling and discuss how the countermeasures can be automatically matched to the security issues discovered in the network.
2021-08-11
Stan, Orly, Cohen, Adi, Elovici, Yuval, Shabtai, Asaf.  2020.  Intrusion Detection System for the MIL-STD-1553 Communication Bus. IEEE Transactions on Aerospace and Electronic Systems. 56:3010–3027.
MIL-STD-1553 is a military standard that defines the specification of a serial communication bus that has been implemented in military and aerospace avionic platforms for over 40 years. MIL-STD-1553 was designed for a high level of fault tolerance while less attention was paid to cyber security issues. Thus, as indicated in recent studies, it is exposed to various threats. In this article, we suggest enhancing the security of MIL-STD-1553 communication buses by integrating a machine learning-based intrusion detection system (IDS); such anIDS will be capable of detecting cyber attacks in real time. The IDS consists of two modules: 1) a remote terminal (RT) authentication module that detects illegitimately connected components and data transfers and 2) a sequence-based anomaly detection module that detects anomalies in the operation of the system. The IDS showed high detection rates for both normal and abnormal behavior when evaluated in a testbed using real 1553 hardware, as well as a very fast and accurate training process using logs from a real system. The RT authentication module managed to authenticate RTs with +0.99 precision and +0.98 recall; and detect illegitimate component (or a legitimate component that impersonates other components) with +0.98 precision and +0.99 recall. The sequence-based anomaly detection module managed to perfectly detect both normal and abnormal behavior. Moreover, the sequencebased anomaly detection module managed to accurately (i.e., zero false positives) model the normal behavior of a real system in a short period of time ( 22 s).
2019-06-10
Siboni, Shachar, Shabtai, Asaf, Elovici, Yuval.  2018.  An Attack Scenario and Mitigation Mechanism for Enterprise BYOD Environments. SIGAPP Appl. Comput. Rev.. 18:5–21.

The recent proliferation of the Internet of Things (IoT) technology poses major security and privacy concerns. Specifically, the use of personal IoT devices, such as tablets, smartphones, and even smartwatches, as part of the Bring Your Own Device (BYOD) trend, may result in severe network security breaches in enterprise environments. Such devices increase the attack surface by weakening the digital perimeter of the enterprise network and opening new points of entry for malicious activities. In this paper we demonstrate a novel attack scenario in an enterprise environment by exploiting the smartwatch device of an innocent employee. Using a malicious application running on a suitable smartwatch, the device imitates a real Wi-Fi direct printer service in the network. Using this attack scenario, we illustrate how an advanced attacker located outside of the organization can leak/steal sensitive information from the organization by utilizing the compromised smartwatch as a means of attack. An attack mitigation process and countermeasures are suggested in order to limit the capability of the remote attacker to execute the attack on the network, thus minimizing the data leakage by the smartwatch.

2019-05-09
Kravchik, Moshe, Shabtai, Asaf.  2018.  Detecting Cyber Attacks in Industrial Control Systems Using Convolutional Neural Networks. Proceedings of the 2018 Workshop on Cyber-Physical Systems Security and PrivaCy. :72-83.

This paper presents a study on detecting cyber attacks on industrial control systems (ICS) using convolutional neural networks. The study was performed on a Secure Water Treatment testbed (SWaT) dataset, which represents a scaled-down version of a real-world industrial water treatment plant. We suggest a method for anomaly detection based on measuring the statistical deviation of the predicted value from the observed value. We applied the proposed method by using a variety of deep neural network architectures including different variants of convolutional and recurrent networks. The test dataset included 36 different cyber attacks. The proposed method successfully detected 31 attacks with three false positives thus improving on previous research based on this dataset. The results of the study show that 1D convolutional networks can be successfully used for anomaly detection in industrial control systems and outperform recurrent networks in this setting. The findings also suggest that 1D convolutional networks are effective at time series prediction tasks which are traditionally considered to be best solved using recurrent neural networks. This observation is a promising one, as 1D convolutional neural networks are simpler, smaller, and faster than the recurrent neural networks.

2018-11-28
Sachidananda, Vinay, Siboni, Shachar, Shabtai, Asaf, Toh, Jinghui, Bhairav, Suhas, Elovici, Yuval.  2017.  Let the Cat Out of the Bag: A Holistic Approach Towards Security Analysis of the Internet of Things. Proceedings of the 3rd ACM International Workshop on IoT Privacy, Trust, and Security. :3–10.

The exponential increase of Internet of Things (IoT) devices have resulted in a range of new and unanticipated vulnerabilities associated with their use. IoT devices from smart homes to smart enterprises can easily be compromised. One of the major problems associated with the IoT is maintaining security; the vulnerable nature of IoT devices poses a challenge to many aspects of security, including security testing and analysis. It is trivial to perform the security analysis for IoT devices to understand the loop holes and very nature of the devices itself. Given these issues, there has been less emphasis on security testing and analysis of the IoT. In this paper, we show our preliminary efforts in the area of security analysis for IoT devices and introduce a security IoT testbed for performing security analysis. We also discuss the necessary design, requirements and the architecture to support our security analysis conducted via the proposed testbed.

2018-03-19
Guarnizo, Juan David, Tambe, Amit, Bhunia, Suman Sankar, Ochoa, Martin, Tippenhauer, Nils Ole, Shabtai, Asaf, Elovici, Yuval.  2017.  SIPHON: Towards Scalable High-Interaction Physical Honeypots. Proceedings of the 3rd ACM Workshop on Cyber-Physical System Security. :57–68.

In recent years, the emerging Internet-of-Things (IoT) has led to rising concerns about the security of networked embedded devices. In this work, we propose the SIPHON architecture–-a Scalable high-Interaction Honeypot platform for IoT devices. Our architecture leverages IoT devices that are physically at one location and are connected to the Internet through so-called $\backslash$emph\wormholes\ distributed around the world. The resulting architecture allows exposing few physical devices over a large number of geographically distributed IP addresses. We demonstrate the proposed architecture in a large scale experiment with 39 wormhole instances in 16 cities in 9 countries. Based on this setup, five physical IP cameras, one NVR and one IP printer are presented as 85 real IoT devices on the Internet, attracting a daily traffic of 700MB for a period of two months. A preliminary analysis of the collected traffic indicates that devices in some cities attracted significantly more traffic than others (ranging from 600 000 incoming TCP connections for the most popular destination to less than 50 000 for the least popular). We recorded over 400 brute-force login attempts to the web-interface of our devices using a total of 1826 distinct credentials, from which 11 attempts were successful. Moreover, we noted login attempts to Telnet and SSH ports some of which used credentials found in the recently disclosed Mirai malware.

2017-06-05
Mirsky, Yisroel, Shabtai, Asaf, Rokach, Lior, Shapira, Bracha, Elovici, Yuval.  2016.  SherLock vs Moriarty: A Smartphone Dataset for Cybersecurity Research. Proceedings of the 2016 ACM Workshop on Artificial Intelligence and Security. :1–12.

In this paper we describe and share with the research community, a significant smartphone dataset obtained from an ongoing long-term data collection experiment. The dataset currently contains 10 billion data records from 30 users collected over a period of 1.6 years and an additional 20 users for 6 months (totaling 50 active users currently participating in the experiment). The experiment involves two smartphone agents: SherLock and Moriarty. SherLock collects a wide variety of software and sensor data at a high sample rate. Moriarty perpetrates various attacks on the user and logs its activities, thus providing labels for the SherLock dataset. The primary purpose of the dataset is to help security professionals and academic researchers in developing innovative methods of implicitly detecting malicious behavior in smartphones. Specifically, from data obtainable without superuser (root) privileges. To demonstrate possible uses of the dataset, we perform a basic malware analysis and evaluate a method of continuous user authentication.

2017-05-18
Schweitzer, Nadav, Stulman, Ariel, Shabtai, Asaf.  2016.  Neighbor Contamination to Achieve Complete Bottleneck Control. Proceedings of the 19th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems. :247–253.

Black-holes, gray-holes and, wormholes, are devastating to the correct operation of any network. These attacks (among others) are based on the premise that packets will travel through compromised nodes, and methods exist to coax routing into these traps. Detection of these attacks are mainly centered around finding the subversion in action. In networks, bottleneck nodes -- those that sit on many potential routes between sender and receiver -- are an optimal location for compromise. Finding naturally occurring path bottlenecks, however, does not entitle network subversion, and as such are more difficult to detect. The dynamic nature of mobile ad-hoc networks (manets) causes ubiquitous routing algorithms to be even more susceptible to this class of attacks. Finding perceived bottlenecks in an olsr based manet, is able to capture between 50%-75% of data. In this paper we propose a method of subtly expanding perceived bottlenecks into complete bottlenecks, raising capture rate up to 99%; albeit, at high cost. We further tune the method to reduce cost, and measure the corresponding capture rate.