Detecting Selected Network Covert Channels Using Machine Learning

International audienceNetwork covert channels break a computer's security policy to establish a stealthy communication. They are a threat being increasingly used by malicious software. Most previous studies on detecting network covert channels using Machine Learning (ML) were tested with a dataset that was created using one single covert channel tool and also are ineffective at classifying covert channels into patterns. In this paper, selected ML methods are applied to detect popular network covert channels. The capacity of detecting and classifying covert channels with high precision is demonstrated. A dataset was created from nine standard covert channel tools and the covert channels are then accordingly classified into patterns and labelled. Half of the generated dataset is used to train three different ML algorithms. The remaining half is used to verify the algorithms' performance. The tested ML algorithms are Support Vector Machines (SVM), k-Nearest Neighbors (k-NN) and Deep Neural Networks (DNN). The k-NN model demonstrated the highest precision rate at 98% detection of a given covert channel and with a low false positive rate of 1%

A Deep Learning Based Approach To Detect Covert Channels Attacks and Anomaly In New Generation Internet Protocol IPv6

The increased dependence of internet-based technologies in all facets of life challenges the government and policymakers with the need for effective shield mechanism against passive and active violations. Following up with the Qatar national vision 2030 activities and its goals for “Achieving Security, stability and maintaining public safety” objectives, the present paper aims to propose a model for safeguarding the information and monitor internet communications effectively. The current study utilizes a deep learning based approach for detecting malicious communications in the network traffic. Considering the efficiency of deep learning in data analysis and classification, a convolutional neural network model was proposed. The suggested model is equipped for detecting attacks in IPv6. The performance of the proposed detection algorithm was validated using a number of datasets, including a newly created dataset. The performance of the model was evaluated for covert channel, DDoS attacks detection in IPv6 and for anomaly detection. The performance assessment produced an accuracy of 100%, 85% and 98% for covert channel detection, DDoS detection and anomaly detection respectively. The project put forward a novel approach for detecting suspicious communications in the network traffic

New intelligent heuristic algorithm to mitigate security vulnerabilities in IPv6

Zero day Cyber-attacks created potential impacts on the way information is held and protected, however one of the vital priorities for governments, agencies and organizations is to secure their network businesses, transactions and communications, simultaneously to avoid security policy and privacy violations under any circumstances. Covert Channel is used to in/ex-filtrate classified data secretly, whereas encryption is used merely to protect communication from being decoded by unauthorized access. In this paper, we propose a new Security Model to mitigate security attacks on legitimate targets misusing IPv6 vulnerabilities. The approach analyses, detects and classifies hidden communication channels through implementing an enhanced feature selection algorithm with a coherent Naive Bayesian Classifier. NBC is one of the most prominent classification algorithm defining the highest probability in data mining area. The proposed framework uses Intelligent Heuristic Algorithm (IHA) to analyse and create a novel primary training data, furthermore a modified Decision Tree C4.5 technique is suggested to classify the richest attribute presenting hidden channels in IPv6 network. The results evaluation showed better detection performance, high accuracy in True Positive Rate (TPR) and a low False Negative Rate (FNR) and a clear attribute ranking

Network-aware Active Wardens in IPv6

Every day the world grows more and more dependent on digital communication. Technologies like e-mail or the World Wide Web that not so long ago were considered experimental, have first become accepted and then indispensable tools of everyday life. New communication technologies built on top of the existing ones continuously race to provide newer and better functionality. Even established communication media like books, radio, or television have become digital in an effort to avoid extinction. In this torrent of digital communication a constant struggle takes place. On one hand, people, organizations, companies and countries attempt to control the ongoing communications and subject them to their policies and laws. On the other hand, there oftentimes is a need to ensure and protect the anonymity and privacy of the very same communications. Neither side in this struggle is necessarily noble or malicious. We can easily imagine that in presence of oppressive censorship two parties might have a legitimate reason to communicate covertly. And at the same time, the use of digital communications for business, military, and also criminal purposes gives equally compelling reasons for monitoring them thoroughly. Covert channels are communication mechanisms that were never intended nor designed to carry information. As such, they are often able to act ``below\u27\u27 the notice of mechanisms designed to enforce security policies. Therefore, using covert channels it might be possible to establish a covert communication that escapes notice of the enforcement mechanism in place. Any covert channel present in digital communications offers a possibility of achieving a secret, and therefore unmonitored, communication. There have been numerous studies investigating possibilities of hiding information in digital images, audio streams, videos, etc. We turn our attention to the covert channels that exist in the digital networks themselves, that is in the digital communication protocols. Currently, one of the most ubiquitous protocols in deployment is the Internet Protocol version 4 (IPv4). Its universal presence and range make it an ideal candidate for covert channel investigation. However, IPv4 is approaching the end of its dominance as its address space nears exhaustion. This imminent exhaustion of IPv4 address space will soon force a mass migration towards Internet Protocol version 6 (IPv6) expressly designed as its successor. While the protocol itself is already over a decade old, its adoption is still in its infancy. The low acceptance of IPv6 results in an insufficient understanding of its security properties. We investigated the protocols forming the foundation of the next generation Internet, Internet Protocol version 6 (IPv6) and Internet Control Message Protocol (ICMPv6) and found numerous covert channels. In order to properly assess their capabilities and performance, we built cctool, a comprehensive covert channel tool. Finally, we considered countermeasures capable of defeating discovered covert channels. For this purpose we extended the previously existing notions of active wardens to equip them with the knowledge of the surrounding network and allow them to more effectively fulfill their role

An approach towards anomaly based detection and profiling covert TCP/IP channels

Firewalls and detection systems have been used for preventing and detecting attacks by a wide variety of mechanisms. A problem has arisen where users and applications can circumvent security policies because of the particularities in the TCP/IP protocol, the ability to obfuscate the data payload, tunnel protocols, and covertly simulate a permitted communication. It has been shown that unusual traffic patterns may lead to discovery of covert channels that employ packet headers. In addition, covert channels can be detected by observing an anomaly in unused packet header fields. Presently, we are not aware of any schemes that address detecting anomalous traffic patterns that can potentially be created by a covert channel. In this work, we will explore the approach of combining anomaly based detection and covert channel profiling to be used for detecting a very precise subset of covert storage channels in network protocols. We shall also discuss why this method is more practical and industry-ready compared to the present research on how to profile and mitigate these types of attacks. Finally, we shall describe a specialized tool to passively monitor networks for these types of attacks and show how it can be used to build an efficient hybrid covert channel and anomaly based detection system

Employing Entropy in the Detection and Monitoring of Network Covert Channels

The detection of covert channels has quickly become a vital need due to their pervasive nature and the increasing popularity of the Internet. In recent years, new and innovative methods have been proposed to aid in the detection of covert channels. Existing detection schemes are often too specific and are ineffective against new covert channels. In this paper, we expound upon previous work done with timing channels and apply it to detecting covert storage channels. Our approach is based on the assumption that the entropy of covert channels will vary from that of previously observed, legitimate, communications. This change in the entropy of a process provides us with a method for identifying storage channels. Using this assumption we created proof of concept code capable of detecting various covert storage channels. The results of our experiments demonstrate that we can successfully detect existing and unpublished covert storage channels accurately

Defensive Cyber Battle Damage Assessment Through Attack Methodology Modeling

Due to the growing sophisticated capabilities of advanced persistent cyber threats, it is necessary to understand and accurately assess cyber attack damage to digital assets. This thesis proposes a Defensive Cyber Battle Damage Assessment (DCBDA) process which utilizes the comprehensive understanding of all possible cyber attack methodologies captured in a Cyber Attack Methodology Exhaustive List (CAMEL). This research proposes CAMEL to provide detailed knowledge of cyber attack actions, methods, capabilities, forensic evidence and evidence collection methods. This product is modeled as an attack tree called the Cyber Attack Methodology Attack Tree (CAMAT). The proposed DCBDA process uses CAMAT to analyze potential attack scenarios used by an attacker. These scenarios are utilized to identify the associated digital forensic methods in CAMEL to correctly collect and analyze the damage from a cyber attack. The results from the experimentation of the proposed DCBDA process show the process can be successfully applied to cyber attack scenarios to correctly assess the extent, method and damage caused by a cyber attack

IPv6: a new security challenge

Tese de mestrado em Segurança Informática, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2011O Protocolo de Internet versão 6 (IPv6) foi desenvolvido com o intuito de resolver alguns dos problemas não endereçados pelo seu antecessor, o Protocolo de Internet versão 4 (IPv4), nomeadamente questões relacionadas com segurança e com o espaço de endereçamento disponível. São muitos os que na última década têm desenvolvido estudos sobre os investimentos necessários à sua adoção e sobre qual o momento certo para que o mesmo seja adotado por todos os players no mercado. Recentemente, o problema da extinção de endereçamentos públicos a ser disponibilizado pelas diversas Region Internet registry – RIRs - despertou o conjunto de entidades envolvidas para que se agilizasse o processo de migração do IPv4 para o IPv6. Ao contrário do IPv4, esta nova versão considera a segurança como um objetivo fundamental na sua implementação, nesse sentido é recomendado o uso do protocolo IPsec ao nível da camada de rede. No entanto, e devido à imaturidade do protocolo e à complexidade que este período de transição comporta, existem inúmeras implicações de segurança que devem ser consideradas neste período de migração. O objetivo principal deste trabalho é definir um conjunto de boas práticas no âmbito da segurança na implementação do IPv6 que possa ser utilizado pelos administradores de redes de dados e pelas equipas de segurança dos diversos players no mercado. Nesta fase de transição, é de todo útil e conveniente contribuir de forma eficiente na interpretação dos pontos fortes deste novo protocolo assim como nas vulnerabilidades a ele associadas.IPv6 was developed to address the exhaustion of IPv4 addresses, but has not yet seen global deployment. Recent trends are now finally changing this picture and IPv6 is expected to take off soon. Contrary to the original, this new version of the Internet Protocol has security as a design goal, for example with its mandatory support for network layer security. However, due to the immaturity of the protocol and the complexity of the transition period, there are several security implications that have to be considered when deploying IPv6. In this project, our goal is to define a set of best practices for IPv6 Security that could be used by IT staff and network administrators within an Internet Service Provider. To this end, an assessment of some of the available security techniques for IPv6 will be made by means of a set of laboratory experiments using real equipment from an Internet Service Provider in Portugal. As the transition for IPv6 seems inevitable this work can help ISPs in understanding the threats that exist in IPv6 networks and some of the prophylactic measures available, by offering recommendations to protect internal as well as customers’ networks