André Ricardo Abed Grégio
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Featured researches published by André Ricardo Abed Grégio.
Data mining, intrusion detection, information assurance, and data networks security 2007 | 2007
André Ricardo Abed Grégio; Rafael D. C. Santos; Antonio Montes
As the amount and types of remote network services increase, the analysis of their logs has become a very difficult and time consuming task. There are several ways to filter relevant information and provide a reduced log set for analysis, such as whitelisting and intrusion detection tools, but all of them require too much fine- tuning work and human expertise. Nowadays, researchers are evaluating data mining approaches for intrusion detection in network logs, using techniques such as genetic algorithms, neural networks, clustering algorithms, etc. Some of those techniques yield good results, yet requiring a very large number of attributes gathered by network traffic to detect useful information. In this work we apply and evaluate some data mining techniques (K-Nearest Neighbors, Artificial Neural Networks and Decision Trees) in a reduced number of attributes on some log data sets acquired from a real network and a honeypot, in order to classify traffic logs as normal or suspicious. The results obtained allow us to identify unlabeled logs and to describe which attributes were used for the decision. This approach provides a very reduced amount of logs to the network administrator, improving the analysis task and aiding in discovering new kinds of attacks against their networks.
Proceedings of SPIE | 2011
André Ricardo Abed Grégio; Dario Simões Fernandes Filho; Vitor Monte Afonso; Rafael D. C. Santos; Mario Jino; Paulo Lício de Geus
Malicious code (malware) that spreads through the Internet-such as viruses, worms and trojans-is a major threat to information security nowadays and a profitable business for criminals. There are several approaches to analyze malware by monitoring its actions while it is running in a controlled environment, which helps to identify malicious behaviors. In this article we propose a tool to analyze malware behavior in a non-intrusive and effective way, extending the analysis possibilities to cover malware samples that bypass current approaches and also fixes some issues with these approaches.
information security and assurance | 2009
André Ricardo Abed Grégio; Isabela L. Oliveira; Rafael D. C. Santos; Adriano Mauro Cansian; Paulo Lício de Geus
Malware has become a major threat in the last years due to the ease of spread through the Internet. Malware detection has become difficult with the use of compression, polymorphic methods and techniques to detect and disable security software. Those and other obfuscation techniques pose a problem for detection and classification schemes that analyze malware behavior. In this paper we propose a distributed architecture to improve malware collection using different honeypot technologies to increase the variety of malware collected. We also present a daemon tool developed to grab malware distributed through spam and a pre-classification technique that uses antivirus technology to separate malware in generic classes.
Applied Ontology | 2016
André Ricardo Abed Grégio; Rodrigo Bonacin; Antonio Carlos de Marchi; Olga Nabuco; Paulo Lício de Geus
–Malicious programs have been the main actors in complex, sophisticated attacks against nations, governments, diplomatic agencies, private institutions and people. Knowledge about malicious program behavior forms the basis for constructing more secure information systems. In this article, we introduce MBO, a Malicious Behavior Ontology that represents complex behaviors of suspicious executions, and through inference rules calculates their associated threat level for analytical proposals. We evaluate MBO using over two thousand unique known malware and 385 unique known benign software. Results highlight the representativeness of the MBO for expressing typical malicious activities. Security ontologyMalware behaviorThreat analysis
international conference on communications | 2012
Vitor Monte Afonso; Dario Simões Fernandes Filho; André Ricardo Abed Grégio; Paulo Lício de Geus; Mario Jino
Malicious programs (malware) cause serious security issues to home users and even to highly secured enterprise systems. The main infection vector currently used by attackers is the Internet. To improve the detection rate and to develop protection mechanisms, it is very important to analyze and study these threats. To this end, several systems were developed to perform malware analysis, which support operating system (OS) programs or Web codes, but they all suffer from limitations. Also, the existing systems focus only on one type of malware, those that target the OS or that require a Web browser. In this article, we propose a framework that is able to analyze Web and OS-based malware, which provides better detection rates and a broader range of malware types analysis. We have also evaluated and compared our analysis results to the state-of-the-art systems, presenting the advantages of the developed framework over them when regarding Web and OS-based malware.
international conference on computational science and its applications | 2012
Isabela L. Oliveira; André Ricardo Abed Grégio; Adriano Mauro Cansian
Malicious programs (malware) can cause severe damage on computer systems and data. The mechanism that the human immune system uses to detect and protect from organisms that threaten the human body is efficient and can be adapted to detect malware attacks. In this paper we propose a system to perform malware distributed collection, analysis and detection, this last inspired by the human immune system. After collecting malware samples from Internet, they are dynamically analyzed so as to provide execution traces at the operating system level and network flows that are used to create a behavioral model and to generate a detection signature. Those signatures serve as input to a malware detector, acting as the antibodies in the antigen detection process. This allows us to understand the malware attack and aids in the infection removal procedures.
The Second International Conference on Forensic Computer Science | 2007
Marcelo Sacchetin; André Ricardo Abed Grégio; Luiz Duarte; Antonio Montes
We discuss some techniques currently used by intruders to control groups of compromised machines (botnets). We show how honeynets can be used to identify, monitor and understand the behavior of botnets. We describe a real attack in detail, illustrating analysis techniques developed specifically for botnets. The tools, network topology and strategies we describe can easily be adopted by other researchers and the network security community.
international conference on computational science and its applications | 2012
André Ricardo Abed Grégio; Vitor Monte Afonso; Dario Simões Fernandes Filho; Paulo Lício de Geus; Mario Jino; Rafael D. C. Santos
Malicious programs pose a major threat to Internet-connected systems, increasing the importance of studying their behavior in order to fight against them. In this paper, we propose definitions to the different types of behavior that a program can present during its execution. Based on those definitions, we define suspicious behavior as the group of actions that change the state of a target system. We also propose a set of network and system-level dangerous activities that can be used to denote the malignity in suspicious behaviors, which were extracted from a large set of malware samples. In addition, we evaluate the malware samples according to their suspicious behavior. Moreover, we developed filters to translate from lower-level execution traces to the observed dangerous activities and evaluated them in the context of actual malware.
Proceedings of SPIE | 2012
Rafael D. C. Santos; André Ricardo Abed Grégio; Jordan Raddick; Vamsi Vattki; Alexander S. Szalay
SkyServer is an Internet portal to data from the Sloan Digital Sky Survey, the largest online archive of astronomy data in the world. provides free access to hundreds of millions of celestial objects for science, education and outreach purposes. Logs of accesses to SkyServer comprise around 930 million hits, 140 million web services accesses and 170 million SQL submitted queries, collected over the past 10 years. These logs also contain indications of compromise attempts on the servers. In this paper, we show some threats that were detected in ten years of stored logs, and compare them with known threats in those years. Also, we present an analysis of the evolution of those threats over these years.
Proceedings of SPIE | 2011
André Ricardo Abed Grégio; Rafael D. C. Santos
Malware spread via Internet is a great security threat, so studying their behavior is important to identify and classify them. Using SSDT hooking we can obtain malware behavior by running it in a controlled environment and capturing interactions with the target operating system regarding file, process, registry, network and mutex activities. This generates a chain of events that can be used to compare them with other known malware. In this paper we present a simple approach to convert malware behavior into activity graphs and show some visualization techniques that can be used to analyze malware behavior, individually or grouped.