Análise de malware com suporte de hardware

Orientadores: Paulo Lício de Geus, André Ricardo Abed GrégioDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de ComputaçãoResumo: O mundo atual é impulsionado pelo uso de sistemas computacionais, estando estes pre- sentes em todos aspectos da vida cotidiana. Portanto, o correto funcionamento destes é essencial para se assegurar a manutenção das possibilidades trazidas pelos desenvolvi- mentos tecnológicos. Contudo, garantir o correto funcionamento destes não é uma tarefa fácil, dado que indivíduos mal-intencionados tentam constantemente subvertê-los visando benefíciar a si próprios ou a terceiros. Os tipos mais comuns de subversão são os ataques por códigos maliciosos (malware), capazes de dar a um atacante controle total sobre uma máquina. O combate à ameaça trazida por malware baseia-se na análise dos artefatos coletados de forma a permitir resposta aos incidentes ocorridos e o desenvolvimento de contramedidas futuras. No entanto, atacantes têm se especializado em burlar sistemas de análise e assim manter suas operações ativas. Para este propósito, faz-se uso de uma série de técnicas denominadas de "anti-análise", capazes de impedir a inspeção direta dos códigos maliciosos. Dentre essas técnicas, destaca-se a evasão do processo de análise, na qual são empregadas exemplares capazes de detectar a presença de um sistema de análise para então esconder seu comportamento malicioso. Exemplares evasivos têm sido cada vez mais utilizados em ataques e seu impacto sobre a segurança de sistemas é considerá- vel, dado que análises antes feitas de forma automática passaram a exigir a supervisão de analistas humanos em busca de sinais de evasão, aumentando assim o custo de se manter um sistema protegido. As formas mais comuns de detecção de um ambiente de análise se dão através da detecção de: (i) código injetado, usado pelo analista para inspecionar a aplicação; (ii) máquinas virtuais, usadas em ambientes de análise por questões de escala; (iii) efeitos colaterais de execução, geralmente causados por emuladores, também usados por analistas. Para lidar com malware evasivo, analistas tem se valido de técnicas ditas transparentes, isto é, que não requerem injeção de código nem causam efeitos colaterais de execução. Um modo de se obter transparência em um processo de análise é contar com suporte do hardware. Desta forma, este trabalho versa sobre a aplicação do suporte de hardware para fins de análise de ameaças evasivas. No decorrer deste texto, apresenta-se uma avaliação das tecnologias existentes de suporte de hardware, dentre as quais máqui- nas virtuais de hardware, suporte de BIOS e monitores de performance. A avaliação crítica de tais tecnologias oferece uma base de comparação entre diferentes casos de uso. Além disso, são enumeradas lacunas de desenvolvimento existentes atualmente. Mais que isso, uma destas lacunas é preenchida neste trabalho pela proposição da expansão do uso dos monitores de performance para fins de monitoração de malware. Mais especificamente, é proposto o uso do monitor BTS para fins de construção de um tracer e um debugger. O framework proposto e desenvolvido neste trabalho é capaz, ainda, de lidar com ataques do tipo ROP, um dos mais utilizados atualmente para exploração de vulnerabilidades. A avaliação da solução demonstra que não há a introdução de efeitos colaterais, o que per- mite análises de forma transparente. Beneficiando-se desta característica, demonstramos a análise de aplicações protegidas e a identificação de técnicas de evasãoAbstract: Today¿s world is driven by the usage of computer systems, which are present in all aspects of everyday life. Therefore, the correct working of these systems is essential to ensure the maintenance of the possibilities brought about by technological developments. However, ensuring the correct working of such systems is not an easy task, as many people attempt to subvert systems working for their own benefit. The most common kind of subversion against computer systems are malware attacks, which can make an attacker to gain com- plete machine control. The fight against this kind of threat is based on analysis procedures of the collected malicious artifacts, allowing the incident response and the development of future countermeasures. However, attackers have specialized in circumventing analysis systems and thus keeping their operations active. For this purpose, they employ a series of techniques called anti-analysis, able to prevent the inspection of their malicious codes. Among these techniques, I highlight the analysis procedure evasion, that is, the usage of samples able to detect the presence of an analysis solution and then hide their malicious behavior. Evasive examples have become popular, and their impact on systems security is considerable, since automatic analysis now requires human supervision in order to find evasion signs, which significantly raises the cost of maintaining a protected system. The most common ways for detecting an analysis environment are: i) Injected code detec- tion, since injection is used by analysts to inspect applications on their way; ii) Virtual machine detection, since they are used in analysis environments due to scalability issues; iii) Execution side effects detection, usually caused by emulators, also used by analysts. To handle evasive malware, analysts have relied on the so-called transparent techniques, that is, those which do not require code injection nor cause execution side effects. A way to achieve transparency in an analysis process is to rely on hardware support. In this way, this work covers the application of the hardware support for the evasive threats analysis purpose. In the course of this text, I present an assessment of existing hardware support technologies, including hardware virtual machines, BIOS support, performance monitors and PCI cards. My critical evaluation of such technologies provides basis for comparing different usage cases. In addition, I pinpoint development gaps that currently exists. More than that, I fill one of these gaps by proposing to expand the usage of performance monitors for malware monitoring purposes. More specifically, I propose the usage of the BTS monitor for the purpose of developing a tracer and a debugger. The proposed framework is also able of dealing with ROP attacks, one of the most common used technique for remote vulnerability exploitation. The framework evaluation shows no side-effect is introduced, thus allowing transparent analysis. Making use of this capability, I demonstrate how protected applications can be inspected and how evasion techniques can be identifiedMestradoCiência da ComputaçãoMestre em Ciência da ComputaçãoCAPE

Architecture de sécurité de bout en bout et mécanismes d'autoprotection pour les environnements Cloud

Since several years the virtualization of infrastructures became one of the major research challenges, consuming less energy while delivering new services. However, many attacks hinder the global adoption of Cloud computing. Self-protection has recently raised growing interest as possible element of answer to the cloud computing infrastructure protection challenge. Yet, previous solutions fall at the last hurdle as they overlook key features of the cloud, by lack of flexible security policies, cross-layered defense, multiple control granularities, and open security architectures. This thesis presents VESPA, a self-protection architecture for cloud infrastructures. Flexible coordination between self-protection loops allows enforcing a rich spectrum of security strategies. A multi-plane extensible architecture also enables simple integration of commodity security components.Recently, some of the most powerful attacks against cloud computing infrastructures target the Virtual Machine Monitor (VMM). In many case, the main attack vector is a poorly confined device driver. Current architectures offer no protection against such attacks. This thesis proposes an altogether different approach by presenting KungFuVisor, derived from VESPA, a framework to build self-defending hypervisors. The result is a very flexible self-protection architecture, enabling to enforce dynamically a rich spectrum of remediation actions over different parts of the VMM, also facilitating defense strategy administration. We showed the application to three different protection scheme: virus infection, mobile clouds and hypervisor drivers. Indeed VESPA can enhance cloud infrastructure securityLa virtualisation des infrastructures est devenue un des enjeux majeurs dans la recherche, qui fournissent des consommations d'énergie moindres et des nouvelles opportunités. Face à de multiples menaces et des mécanismes de défense hétérogènes, l'approche autonomique propose une gestion simplifiée, robuste et plus efficace de la sécurité du cloud. Aujourd'hui, les solutions existantes s'adaptent difficilement. Il manque des politiques de sécurité flexibles, une défense multi-niveaux, des contrôles à granularité variable, ou encore une architecture de sécurité ouverte. Ce mémoire présente VESPA, une architecture d'autoprotection pour les infrastructures cloud. VESPA est construit autour de politiques qui peuvent réguler la sécurité à plusieurs niveaux. La coordination flexible entre les boucles d'autoprotection réalise un large spectre de stratégies de sécurité comme des détections et des réactions sur plusieurs niveaux. Une architecture extensible multi plans permet d'intégrer simplement des éléments déjà présents. Depuis peu, les attaques les plus critiques contre les infrastructures cloud visent la brique la plus sensible: l'hyperviseur. Le vecteur d'attaque principal est un pilote de périphérique mal confiné. Les mécanismes de défense mis en jeu sont statiques et difficile à gérer. Nous proposons une approche différente avec KungFuVisor, un canevas logiciel pour créer des hyperviseurs autoprotégés spécialisant l'architecture VESPA. Nous avons montré son application à trois types de protection différents : les attaques virales, la gestion hétérogène multi-domaines et l'hyperviseur. Ainsi la sécurité des infrastructures cloud peut être améliorée grâce à VESP

Secure Virtualization of Latency-Constrained Systems

Virtualization is a mature technology in server and desktop environments where multiple systems are consolidate onto a single physical hardware platform, increasing the utilization of todays multi-core systems as well as saving resources such as energy, space and costs compared to multiple single systems. Looking at embedded environments reveals that many systems use multiple separate computing systems inside, including requirements for real-time and isolation properties. For example, modern high-comfort cars use up to a hundred embedded computing systems. Consolidating such diverse configurations promises to save resources such as energy and weight. In my work I propose a secure software architecture that allows consolidating multiple embedded software systems with timing constraints. The base of the architecture builds a microkernel-based operating system that supports a variety of different virtualization approaches through a generic interface, supporting hardware-assisted virtualization and paravirtualization as well as multiple architectures. Studying guest systems with latency constraints with regards to virtualization showed that standard techniques such as high-frequency time-slicing are not a viable approach. Generally, guest systems are a combination of best-effort and real-time work and thus form a mixed-criticality system. Further analysis showed that such systems need to export relevant internal scheduling information to the hypervisor to support multiple guests with latency constraints. I propose a mechanism to export those relevant events that is secure, flexible, has good performance and is easy to use. The thesis concludes with an evaluation covering the virtualization approach on the ARM and x86 architectures and two guest operating systems, Linux and FreeRTOS, as well as evaluating the export mechanism

CLOUD COMPUTING MADE EASY

Cloud computing is the delivery of computing as a service rather than as a product, where by shared resources software and information are provided to computer are other device as a utility over a network. In a cloud computing system, there is a significant workload shift. Local computers no longer have to do all the heavy lifting, when it comes to running applications. The network of computers that makeup the cloud handles them instead. Hardware and software demand on the users side decrease. The only thing the users’ computer needs to be able to run is the cloud computing systems interface software, which can be as simple as a web browser and the clouds network take care of the rest. This article is prepared based on the Author’s teaching the subject for M.Tech level recent years, keeping in view of VTU Syllabus in particular

Measuring the Semantic Integrity of a Process Self

The focus of the thesis is the definition of a framework to protect a process from attacks against the process self, i.e. attacks that alter the expected behavior of the process, by integrating static analysis and run-time monitoring. The static analysis of the program returns a description of the process self that consists of a context-free grammar, which defines the legal system call traces, and a set of invariants on process variables that hold when a system call is issued. Run-time monitoring assures the semantic integrity of the process by checking that its behavior is coherent with the process self returned by the static analysis. The proposed framework can also cover kernel integrity to protect the process from attacks from the kernel-level. The implementation of the run-time monitoring is based upon introspection, a technique that analyzes the state of a computer to rebuild and check the consistency of kernel or user-level data structures. The ability of observing the run-time values of variables reduces the complexity of the static analysis and increases the amount of information that can be extracted on the run-time behavior of the process. To achieve transparency of the controls for the process while avoiding the introduction of special purpose hardware units that access the memory, the architecture of the run-time monitoring adopts virtualization technology and introduces two virtual machines, the monitored and the introspection virtual machines. This approach increases the overall robustness because a distinct virtual machine, the introspection virtual machine, applies introspection in a transparent way both to verify the kernel integrity and to retrieve the status of the process to check the process self. After presenting the framework and its implementation, the thesis discusses some of its applications to increase the security of a computer network. The first application of the proposed framework is the remote attestation of the semantic integrity of a process. Then, the thesis describes a set of extensions to the framework to protect a process from physical attacks by running an obfuscated version of the process code. Finally, the thesis generalizes the framework to support the efficient sharing of an information infrastructure among users and applications with distinct security and reliability requirements by introducing highly parallel overlays

Cyber Security

This open access book constitutes the refereed proceedings of the 16th International Annual Conference on Cyber Security, CNCERT 2020, held in Beijing, China, in August 2020. The 17 papers presented were carefully reviewed and selected from 58 submissions. The papers are organized according to the following topical sections: access control; cryptography; denial-of-service attacks; hardware security implementation; intrusion/anomaly detection and malware mitigation; social network security and privacy; systems security

Securing Virtualized System via Active Protection

Virtualization is the predominant enabling technology of current cloud infrastructure

OSS architecture for mixed-criticality systems – a dual view from a software and system engineering perspective

Computer-based automation in industrial appliances led to a growing number of logically dependent, but physically separated embedded control units per appliance. Many of those components are safety-critical systems, and require adherence to safety standards, which is inconsonant with the relentless demand for features in those appliances. Features lead to a growing amount of control units per appliance, and to a increasing complexity of the overall software stack, being unfavourable for safety certifications. Modern CPUs provide means to revise traditional separation of concerns design primitives: the consolidation of systems, which yields new engineering challenges that concern the entire software and system stack. Multi-core CPUs favour economic consolidation of formerly separated systems with one efficient single hardware unit. Nonetheless, the system architecture must provide means to guarantee the freedom from interference between domains of different criticality. System consolidation demands for architectural and engineering strategies to fulfil requirements (e.g., real-time or certifiability criteria) in safety-critical environments. In parallel, there is an ongoing trend to substitute ordinary proprietary base platform software components by mature OSS variants for economic and engineering reasons. There are fundamental differences of processual properties in development processes of OSS and proprietary software. OSS in safety-critical systems requires development process assessment techniques to build an evidence-based fundament for certification efforts that is based upon empirical software engineering methods. In this thesis, I will approach from both sides: the software and system engineering perspective. In the first part of this thesis, I focus on the assessment of OSS components: I develop software engineering techniques that allow to quantify characteristics of distributed OSS development processes. I show that ex-post analyses of software development processes can be used to serve as a foundation for certification efforts, as it is required for safety-critical systems. In the second part of this thesis, I present a system architecture based on OSS components that allows for consolidation of mixed-criticality systems on a single platform. Therefore, I exploit virtualisation extensions of modern CPUs to strictly isolate domains of different criticality. The proposed architecture shall eradicate any remaining hypervisor activity in order to preserve real-time capabilities of the hardware by design, while guaranteeing strict isolation across domains.Computergestützte Automatisierung industrieller Systeme führt zu einer wachsenden Anzahl an logisch abhängigen, aber physisch voneinander getrennten Steuergeräten pro System. Viele der Einzelgeräte sind sicherheitskritische Systeme, welche die Einhaltung von Sicherheitsstandards erfordern, was durch die unermüdliche Nachfrage an Funktionalitäten erschwert wird. Diese führt zu einer wachsenden Gesamtzahl an Steuergeräten, einhergehend mit wachsender Komplexität des gesamten Softwarekorpus, wodurch Zertifizierungsvorhaben erschwert werden. Moderne Prozessoren stellen Mittel zur Verfügung, welche es ermöglichen, das traditionelle >Trennung von Belangen< Designprinzip zu erneuern: die Systemkonsolidierung. Sie stellt neue ingenieurstechnische Herausforderungen, die den gesamten Software und Systemstapel betreffen. Mehrkernprozessoren begünstigen die ökonomische und effiziente Konsolidierung vormals getrennter Systemen zu einer effizienten Hardwareeinheit. Geeignete Systemarchitekturen müssen jedoch die Rückwirkungsfreiheit zwischen Domänen unterschiedlicher Kritikalität sicherstellen. Die Konsolidierung erfordert architektonische, als auch ingenieurstechnische Strategien um die Anforderungen (etwa Echtzeit- oder Zertifizierbarkeitskriterien) in sicherheitskritischen Umgebungen erfüllen zu können. Zunehmend werden herkömmliche proprietär entwickelte Basisplattformkomponenten aus ökonomischen und technischen Gründen vermehrt durch ausgereifte OSS Alternativen ersetzt. Jedoch hindern fundamentale Unterschiede bei prozessualen Eigenschaften des Entwicklungsprozesses bei OSS den Einsatz in sicherheitskritischen Systemen. Dieser erfordert Techniken, welche es erlauben die Entwicklungsprozesse zu bewerten um ein evidenzbasiertes Fundament für Zertifizierungsvorhaben basierend auf empirischen Methoden des Software Engineerings zur Verfügung zu stellen. In dieser Arbeit nähere ich mich von beiden Seiten: der Softwaretechnik, und der Systemarchitektur. Im ersten Teil befasse ich mich mit der Beurteilung von OSS Komponenten: Ich entwickle Softwareanalysetechniken, welche es ermöglichen, prozessuale Charakteristika von verteilten OSS Entwicklungsvorhaben zu quantifizieren. Ich zeige, dass rückschauende Analysen des Entwicklungsprozess als Grundlage für Softwarezertifizierungsvorhaben genutzt werden können. Im zweiten Teil dieser Arbeit widme ich mich der Systemarchitektur. Ich stelle eine OSS-basierte Systemarchitektur vor, welche die Konsolidierung von Systemen gemischter Kritikalität auf einer alleinstehenden Plattform ermöglicht. Dazu nutze ich Virtualisierungserweiterungen moderner Prozessoren aus, um die Hardware in strikt voneinander isolierten Rechendomänen unterschiedlicher Kritikalität unterteilen zu können. Die vorgeschlagene Architektur soll jegliche Betriebsstörungen des Hypervisors beseitigen, um die Echtzeitfähigkeiten der Hardware bauartbedingt aufrecht zu erhalten, während strikte Isolierung zwischen Domänen stets sicher gestellt ist

Secure policies for the distributed virtual machines in mobile cloud computing

Mobile Cloud Computing (MCC) is a combination of cloud computing and mobile computing through wireless technology in order to overcome mobile devices' resource limitations. In MCC, virtualization plays a key role whereas the cloud resources are shared among many users to help them achieve an efficient performance and exploiting the maximum capacity of the cloud’s servers. However, the lack of security aspect impedes the benefits of virtualization techniques, whereby malicious users can violate and damage sensitive data in distributed Virtual Machines (VMs). Thus, this study aims to provide protection of distributed VMs and mobile user’s sensitive data in terms of security and privacy. This study proposes an approach based on cloud proxy known as Proxy-3S that combines three security policies for VMs; user’s access control, secure allocation, and secure communication. The Proxy-3S keeps the distributed VMs safe in different servers on the cloud. It enhances the grants access authorization for permitted distributed intensive applications’ tasks. Furthermore, an algorithm that enables secure communication among distributed VMs and protection of sensitive data in VMs on the cloud is proposed. A prototype is implemented on a NetworkCloudSim simulator to manage VMs security and data confidentiality automatically. Several experiments were conducted using real-world healthcare distributed application in terms of efficiency, coverage and execution time. The experiments show that the proposed approach achieved lower attacker’s efficiency and coverage ratios; equal to 0.35 and 0.41 respectively in all experimented configurations compared with existing works. In addition, the execution time of the proposed approach is satisfactory ranging from 441ms to 467ms of small and large cloud configurations. This study serves to provide integrity and confidentiality in exchanging sensitive information among multistakeholder in distributed mobile applications