An Iterative and Toolchain-Based Approach to Automate Scanning and Mapping Computer Networks

As today's organizational computer networks are ever evolving and becoming more and more complex, finding potential vulnerabilities and conducting security audits has become a crucial element in securing these networks. The first step in auditing a network is reconnaissance by mapping it to get a comprehensive overview over its structure. The growing complexity, however, makes this task increasingly effortful, even more as mapping (instead of plain scanning), presently, still involves a lot of manual work. Therefore, the concept proposed in this paper automates the scanning and mapping of unknown and non-cooperative computer networks in order to find security weaknesses or verify access controls. It further helps to conduct audits by allowing comparing documented with actual networks and finding unauthorized network devices, as well as evaluating access control methods by conducting delta scans. It uses a novel approach of augmenting data from iteratively chained existing scanning tools with context, using genuine analytics modules to allow assessing a network's topology instead of just generating a list of scanned devices. It further contains a visualization model that provides a clear, lucid topology map and a special graph for comparative analysis. The goal is to provide maximum insight with a minimum of a priori knowledge.Comment: 7 pages, 6 figure

A characteristic-based visual analytics approach to detect subtle attacks from NetFlow records

Security is essentially important for any enterprise networks. Denial of service, port scanning, and data exfiltration are among of the most common network intrusions. It\u27s urgent for network administrators to detect such attacks effectively and efficiently from network traffic. Though there are many intrusion detection systems (IDSs) and approaches, Visual Analytics (VA) provides a human-friendly approach to detect network intrusions with situational awareness functionality. Overview visualization is the first and most important step in a VA approach. However, many VA systems cannot effectively identify subtle attacks from massive traffic data because of the incapability of overview visualizations. In this work, we developed two overviews and tried to identify subtle attacks directly from these two overviews. Moreover, zoomed-in visualizations were also provided for further investigation. The primary data source was NetFlow and we evaluated the VA system with datasets from Mini Challenge 3 of VAST challenge 2013. Evaluation results indicated that the VA system can detect all the labeled intrusions (denial of service, port scanning and data exfiltration) with very few false alerts

Segmentation and Model Generation for Large-Scale Cyber Attacks

Raw Cyber attack traffic can present more questions than answers to security analysts. Especially with large-scale observables it is difficult to identify which packets are relevant and what attack behaviors are present. Many existing works in Host or Flow Clustering attempt to group similar behaviors to expedite analysis; these works often phrase the problem directly as offline unsupervised machine learning. This work proposes online processing to simultaneously model coordinating actors and segment traffic that is relevant to a target of interest, all while it is being received. The goal is not just to aggregate similar attack behaviors, but to provide situational awareness by grouping potential coordinators and isolating an attack area of interest around a particular target. The clustering problem is recast as a supervised learning problem: classifying received traffic to the most likely attack model, and iteratively introducing new attack models to explain received traffic. A novel graphical prior probability is defined based on the macroscopic attack structure to improve classification. Malicious traffic captures provided by the Cooperative Association for Internet Data Analysis are used to demonstrate the accuracy of the online model generation and segmentation

Fuzzy intrusion detection

Visual data mining techniques are used to assess which metrics are most effective at detecting different types of attacks. The research confirms that data aggregation and data reduction play crucial roles in the formation of the metrics. Once the proper metrics are identified, fuzzy rules are constructed for detecting attacks in several categories. The attack categories are selected to match the different phases that intruders frequently use when attacking a system. A suite of attacks tools is assembled to test the fuzzy rules. The research shows that fuzzy rules applied to good metrics can provide an effective means of detecting a wide variety of network intrusion activity. This research is being used as a proof of concept for the development of system known as the Fuzzy Intrusion Recognition Engine (FIRE).This thesis examines the application of fuzzy systems to the problem of network intrusion detection. Historically, there have been two primary methods of performing intrusion detection: misuse detection and anomaly detection. In misuse detection, a database of attack signatures is maintained that match known intrusion activity. While misuse detection systems are very effective, they require constant updates to the signature database to remain effective or to detect distinctly new attacks. Anomaly detection systems attempt to discover suspicious behavior by comparing system activity against past usage profiles. In this research, network activity is collected and usage profiles established for a variety of metrics. A network data gathering and data analysis tool was developed to create the metrics from the network stream. Great care is given to identifying the metrics that are most suitable for detecting intrusion activity

A Survey on Enterprise Network Security: Asset Behavioral Monitoring and Distributed Attack Detection

Enterprise networks that host valuable assets and services are popular and frequent targets of distributed network attacks. In order to cope with the ever-increasing threats, industrial and research communities develop systems and methods to monitor the behaviors of their assets and protect them from critical attacks. In this paper, we systematically survey related research articles and industrial systems to highlight the current status of this arms race in enterprise network security. First, we discuss the taxonomy of distributed network attacks on enterprise assets, including distributed denial-of-service (DDoS) and reconnaissance attacks. Second, we review existing methods in monitoring and classifying network behavior of enterprise hosts to verify their benign activities and isolate potential anomalies. Third, state-of-the-art detection methods for distributed network attacks sourced from external attackers are elaborated, highlighting their merits and bottlenecks. Fourth, as programmable networks and machine learning (ML) techniques are increasingly becoming adopted by the community, their current applications in network security are discussed. Finally, we highlight several research gaps on enterprise network security to inspire future research.Comment: Journal paper submitted to Elseive