Discovering New Vulnerabilities in Computer Systems

Vulnerability research plays a key role in preventing and defending against malicious computer system exploitations. Driven by a multi-billion dollar underground economy, cyber criminals today tirelessly launch malicious exploitations, threatening every aspect of daily computing. to effectively protect computer systems from devastation, it is imperative to discover and mitigate vulnerabilities before they fall into the offensive parties\u27 hands. This dissertation is dedicated to the research and discovery of new design and deployment vulnerabilities in three very different types of computer systems.;The first vulnerability is found in the automatic malicious binary (malware) detection system. Binary analysis, a central piece of technology for malware detection, are divided into two classes, static analysis and dynamic analysis. State-of-the-art detection systems employ both classes of analyses to complement each other\u27s strengths and weaknesses for improved detection results. However, we found that the commonly seen design patterns may suffer from evasion attacks. We demonstrate attacks on the vulnerabilities by designing and implementing a novel binary obfuscation technique.;The second vulnerability is located in the design of server system power management. Technological advancements have improved server system power efficiency and facilitated energy proportional computing. However, the change of power profile makes the power consumption subjected to unaudited influences of remote parties, leaving the server systems vulnerable to energy-targeted malicious exploit. We demonstrate an energy abusing attack on a standalone open Web server, measure the extent of the damage, and present a preliminary defense strategy.;The third vulnerability is discovered in the application of server virtualization technologies. Server virtualization greatly benefits today\u27s data centers and brings pervasive cloud computing a step closer to the general public. However, the practice of physical co-hosting virtual machines with different security privileges risks introducing covert channels that seriously threaten the information security in the cloud. We study the construction of high-bandwidth covert channels via the memory sub-system, and show a practical exploit of cross-virtual-machine covert channels on virtualized x86 platforms

Security Applications of Formal Language Theory

We present an approach to improving the security of complex, composed systems based on formal language theory, and show how this approach leads to advances in input validation, security modeling, attack surface reduction, and ultimately, software design and programming methodology. We cite examples based on real-world security flaws in common protocols representing different classes of protocol complexity. We also introduce a formalization of an exploit development technique, the parse tree differential attack, made possible by our conception of the role of formal grammars in security. These insights make possible future advances in software auditing techniques applicable to static and dynamic binary analysis, fuzzing, and general reverse-engineering and exploit development. Our work provides a foundation for verifying critical implementation components with considerably less burden to developers than is offered by the current state of the art. It additionally offers a rich basis for further exploration in the areas of offensive analysis and, conversely, automated defense tools and techniques. This report is divided into two parts. In Part I we address the formalisms and their applications; in Part II we discuss the general implications and recommendations for protocol and software design that follow from our formal analysis

Citrus:Orchestrating Security Mechanisms via Adversarial Deception

Despite the Internet being an apex of human achievement for many years, sophisticated targeted attacks are becoming more prevalent than ever before. Large scale data collection using threat sources such as honeypots have recently been employed to gather information relating to these attacks. While this data naturally details attack properties, there exists challenges in extracting the relevant information from vast data sets to provide valuable insight and a standard description of the attack. Traditionally, threats are identified through the use of signatures that are crafted manually through the composition of IOCs (Indicators of Compromise) extracted from telemetry captured during an attack process, which is often administered by an experienced engineer. These signatures have been proven effective in their use by IDSs (Intrusion Detection Systems) to detect emerging threats. However, little research has been made in automating the extraction of emerging IOCs and the generation of corresponding signatures which incorporate host artefacts. In this paper we present Citrus: a novel approach to the generation of signatures by incorporating host based telemetry extracted from honeypot endpoints. Leveraging this visibility at an endpoint grants a detailed understanding of bleeding edge attack tactics, techniques, and procedures gathered from host logs

Application-based authentication on an inter-VM traffic in a Cloud environment

Cloud Computing (CC) is an innovative computing model in which resources are provided as a service over the Internet, on an as-needed basis. It is a large-scale distributed computing paradigm that is driven by economies of scale, in which a pool of abstracted, virtualized, dynamically-scalable, managed computing power, storage, platforms, and services are delivered on demand to external customers over the Internet. Since cloud is often enabled by virtualization and share a common attribute, that is, the allocation of resources, applications, and even OSs, adequate safeguards and security measures are essential. In fact, Virtualization creates new targets for intrusion due to the complexity of access and difficulty in monitoring all interconnection points between systems, applications, and data sets. This raises many questions about the appropriate infrastructure, processes, and strategy for enacting detection and response to intrusion in a Cloud environment. Hence, without strict controls put in place within the Cloud, guests could violate and bypass security policies, intercept unauthorized client data, and initiate or become the target of security attacks. This article shines the light on the issues of security within Cloud Computing, especially inter-VM traffic visibility. In addition, the paper lays the proposition of an Application Based Security (ABS) approach in order to enforce an application-based authentication between VMs, through various security mechanisms, filtering, structures, and policies

Standards and practices necessary to implement a successful security review program for intrusion management systems

Thesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2002Includes bibliographical references (leaves: 84-85)Text in English; Abstract: Turkish and Englishviii, 91 leavesIntrusion Management Systems are being used to prevent the information systems from successful intrusions and their consequences. They also have detection features. They try to detect intrusions, which have passed the implemented measures. Also the recovery of the system after a successful intrusion is made by the Intrusion Management Systems. The investigation of the intrusion is made by Intrusion Management Systems also. These functions can be existent in an intrusion management system model, which has a four layers architecture. The layers of the model are avoidance, assurance, detection and recovery. At the avoidance layer necessary policies, standards and practices are implemented to prevent the information system from successful intrusions. At the avoidance layer, the effectiveness of implemented measures are measured by some test and reviews. At the detection layer the identification of an intrusion or intrusion attempt is made in the real time. The recovery layer is responsible from restoring the information system after a successful intrusion. It has also functions to investigate the intrusion. Intrusion Management Systems are used to protect information and computer assets from intrusions. An organization aiming to protect its assets must use such a system. After the implementation of the system, continuous reviews must be conducted in order to ensure the effectiveness of the measures taken. Such a review can achieve its goal by using principles and standards. In this thesis, the principles necessary to implement a successful review program for Intrusion Management Systems have been developed in the guidance of Generally Accepted System Security Principles (GASSP). These example principles are developed for tools of each Intrusion Management System layer. These tools are firewalls for avoidance layer, vulnerability scanners for assurance layer, intrusion detection systems for detection layer and integrity checkers for recovery layer of Intrusion Management Systems

An Insider Misuse Threat Detection and Prediction Language

Numerous studies indicate that amongst the various types of security threats, the problem of insider misuse of IT systems can have serious consequences for the health of computing infrastructures. Although incidents of external origin are also dangerous, the insider IT misuse problem is difficult to address for a number of reasons. A fundamental reason that makes the problem mitigation difficult relates to the level of trust legitimate users possess inside the organization. The trust factor makes it difficult to detect threats originating from the actions and credentials of individual users. An equally important difficulty in the process of mitigating insider IT threats is based on the variability of the problem. The nature of Insider IT misuse varies amongst organizations. Hence, the problem of expressing what constitutes a threat, as well as the process of detecting and predicting it are non trivial tasks that add up to the multi- factorial nature of insider IT misuse. This thesis is concerned with the process of systematizing the specification of insider threats, focusing on their system-level detection and prediction. The design of suitable user audit mechanisms and semantics form a Domain Specific Language to detect and predict insider misuse incidents. As a result, the thesis proposes in detail ways to construct standardized descriptions (signatures) of insider threat incidents, as means of aiding researchers and IT system experts mitigate the problem of insider IT misuse. The produced audit engine (LUARM – Logging User Actions in Relational Mode) and the Insider Threat Prediction and Specification Language (ITPSL) are two utilities that can be added to the IT insider misuse mitigation arsenal. LUARM is a novel audit engine designed specifically to address the needs of monitoring insider actions. These needs cannot be met by traditional open source audit utilities. ITPSL is an XML based markup that can standardize the description of incidents and threats and thus make use of the LUARM audit data. Its novelty lies on the fact that it can be used to detect as well as predict instances of threats, a task that has not been achieved to this date by a domain specific language to address threats. The research project evaluated the produced language using a cyber-misuse experiment approach derived from real world misuse incident data. The results of the experiment showed that the ITPSL and its associated audit engine LUARM provide a good foundation for insider threat specification and prediction. Some language deficiencies relate to the fact that the insider threat specification process requires a good knowledge of the software applications used in a computer system. As the language is easily expandable, future developments to improve the language towards this direction are suggested

A Comprehensive Survey of Voice over IP Security Research

We present a comprehensive survey of Voice over IP security academic research, using a set of 245 publications forming a closed cross-citation set. We classify these papers according to an extended version of the VoIP Security Alliance (VoIPSA) Threat Taxonomy. Our goal is to provide a roadmap for researchers seeking to understand existing capabilities and to identify gaps in addressing the numerous threats and vulnerabilities present in VoIP systems. We discuss the implications of our findings with respect to vulnerabilities reported in a variety of VoIP products. We identify two specific problem areas (denial of service, and service abuse) as requiring significant more attention from the research community. We also find that the overwhelming majority of the surveyed work takes a black box view of VoIP systems that avoids examining their internal structure and implementation. Such an approach may miss the mark in terms of addressing the main sources of vulnerabilities, i.e., implementation bugs and misconfigurations. Finally, we argue for further work on understanding cross-protocol and cross-mechanism vulnerabilities (emergent properties), which are the byproduct of a highly complex system-of-systems and an indication of the issues in future large-scale systems

Protecting SNMP Through MarketNet

As dependency on information technology becomes more critical so does the need for network computer security. Because of the distributed nature of networks, large-scale information systems are highly vulnerable to negative elements such as intruders and attackers. The types of attack on a system can be diverse and from different sources. Some of the factors contributing to creating an insecure system are the relentless pace of technology, the need for information processing, and the heterogeneity of hardware and software. In addition to these insecurities, the growth and success of e-commerce make networks a desirable target for intruders to steal credit card numbers, bank account balances, and other valuable information. This paper looks at two different security technologies, SNMP v3 and MarketNet, their architectures and how they have been developed to protect network resources and services, such as, internet applications, devices, and other services, against attacks

Trends on Computer Security: Cryptography, User Authentication, Denial of Service and Intrusion Detection

The new generation of security threats has beenpromoted by digital currencies and real-time applications, whereall users develop new ways to communicate on the Internet.Security has evolved in the need of privacy and anonymity forall users and his portable devices. New technologies in everyfield prove that users need security features integrated into theircommunication applications, parallel systems for mobile devices,internet, and identity management. This review presents the keyconcepts of the main areas in computer security and how it hasevolved in the last years. This work focuses on cryptography,user authentication, denial of service attacks, intrusion detectionand firewalls