Mohammed Noraden Alsaleh

CloudExp: A comprehensive cloud computing experimental framework

Abstract Cloud computing is an emerging and fast-growing computing paradigm that has gained great interest from both industry and academia. Consequently, many researchers are actively involved in cloud computing research projects. One major challenge facing cloud computing researchers is the lack of a comprehensive cloud computing experimental tool to use in their studies. This paper introduces CloudExp , a modeling and simulation environment for cloud computing. CloudExp can be used to evaluate a wide spectrum of cloud components such as processing elements, data centers, storage, networking, Service Level Agreement (SLA) constraints, web-based applications, Service Oriented Architecture (SOA), virtualization, management and automation, and Business Process Management (BPM). Moreover, CloudExp introduces the Rain workload generator which emulates real workloads in cloud environments. Also, MapReduce processing model is integrated in CloudExp in order to handle the processing of big data problems.

ConfigChecker: A tool for comprehensive security configuration analytics

Recent studies show that configurations of network access control is one of the most complex and error prone network management tasks. For this reason, network misconfiguration becomes the main source for network unreachablility and vulnerability problems. In this paper, we present a novel approach that models the global end-to-end behavior of access control configurations of the entire network including routers, IPSec, firewalls, and NAT for unicast and multicast packets. Our model represents the network as a state machine where the packet header and location determines the state. The transitions in this model are determined by packet header information, packet location, and policy semantics for the devices being modeled. We encode the semantics of access control policies with Boolean functions using binary decision diagrams (BDDs). We then use computation tree logic (CTL) and symbolic model checking to investigate all future and past states of this packet in the network and verify network reachability and security requirements. Thus, our contributions in this work is the global encoding for network configurations that allows for general reachability and security property-based verification using CTL model checking. We have implemented our approach in a tool called ConfigChecker. While evaluating ConfigChecker, we modeled and verified network configurations with thousands of devices and millions of configuration rules, thus demonstrating the scalability of this approach. We also present a SCAP-based tool on top of ConfigChecker that integrates host and network configuration compliance checking in one model and allows for executing comprehensive analysis queries in order to verify security and risk requirements across the end-to-end network as a single system.

SCAP based configuration analytics for comprehensive compliance checking

Computing systems today have large number of security configuration settings that are designed to offer flexible and robust services. However, incorrect configuration increases the potential of vulnerability and attacks. Security Content Automation Protocol provides a unified mean to automate the process of checking the desktop system compliance using standard interfaces. However, misconfiguration can be identified only if global checking that includes network and desktop configuration is performed, as many of these configurations are highly interdependent. In this work we present a SCAP-based tool that integrates host and network configuration compliance checking in one model and allows for executing comprehensive analysis queries in order to verify security and risk requirements across the end-to-end network as a single system. Our proposed tool translates XCCDF reports generated from SCAP tools into logical objects that can be further composed to create global logical analysis using more advanced security analytic tools such as ConfigChecker and PROLOG-based tools. This project also shows the value of building on the effort of standard tools to improve the state of the art.

Towards a Unified Modeling and Verification of Network and System Security Configurations

Systems and networks access control configuration are usually analyzed independently although they are logically combined to define the end-to-end security property. While systems and applications security policies define access control based on user identity or group, request type and the requested resource, network security policies uses flow information such as host and service addresses for source and destination to define access control. Therefore, both network and systems access control have to be configured consistently in order to enforce end-to-end security policies. Many previous research attempt to verify either side separately, but it does not provide a unified approach to automatically validate the logical consistency between both of them. In this paper, we introduce a cross-layer modeling and verification system that can analyze the configurations and policies across both application and network components as a single unit. It combines policies from different devices as firewalls, NAT, routers and IPSec gateways as well as basic RBAC-based policies of higher service layers. This allows analyzing, for example, firewall polices in the context of application access control and vice versa providing a true end-to-end configuration verification tool. Our model represents the system as a state machine where packet header, service request and location determine the state and transitions that conform with the configuration, device operations, and packet values are established. We encode the model as Boolean functions using binary decision diagrams (BDDs). We used an extended version of computational tree logic (CTL) to provide more useful operators and then use it with symbolic model checking to prove or find counter examples to needed properties.

ROI-Driven Cyber Risk Mitigation Using Host Compliance and Network Configuration

Automated cyber security configuration synthesis is the holy grail of cyber risk management. The effectiveness of cyber security is highly dependent on the appropriate configuration hardening of heterogeneous, yet interdependent, network security devices, such as firewalls, intrusion detection systems, IPSec gateways, and proxies, to minimize cyber risk. However, determining cost-effective security configuration for risk mitigation is a complex decision-making process because it requires considering many different factors including end-hosts’ security weaknesses based on compliance checking, threat exposure due to network connectivity, potential impact/damage, service reachability requirements according to business polices, acceptable usability due to security hardness, and budgetary constraints. Although many automated techniques and tools have been proposed to scan end-host vulnerabilities and verify the policy compliance, existing approaches lack metrics and analytics to identify fine-grained network access control based on comprehensive risk analysis using both the hosts’ compliance reports and network connectivity. In this paper, we present new metrics and a formal framework for automatically assessing the global enterprise risk and determining the most cost-effective security configuration for risk mitigation considering both the end-host security compliance and network connectivity. Our proposed metrics measure the global enterprise risk based on the end-host vulnerabilities and configuration weaknesses, collected through compliance scanning reports, their inter-dependencies, and network reachability. We then use these metrics to automatically generate a set of host-based vulnerability fixes and network access control decisions that mitigates the global network risk to satisfy the desired Return on Investment of cyber security. We solve the problem of cyber risk mitigation based on advanced formal methods using Satisfiability Module Theories, which has shown scalability with large-size networks.

Objective metrics for firewall security: A holistic view

Firewalls are the primary security devices in cyber defense. Yet, the security of firewalls depends on the quality of protection provided by the firewall policy. The lack of metrics and attack incident data makes measuring the security of firewall policies a challenging task. In this paper, we present a new set of quantitative metrics that can be used to measure, as well as, compare the security level of firewall policies in an enterprise network. The proposed metrics measure the risk of attacks on the network that is imposed due to weaknesses in the firewall policy. We also measure the feasibility of mitigating or removing that risk. The presented metrics are proven to be (1) valid as compared with the ground truth, and (2) practically useful as each one implies actionable security hardening.

Towards Automated Verification of Active Cyber Defense Strategies on Software Defined Networks

Active Cyber Defense (ACD) reconfigures cyber systems (networks and hosts) in timely manner in order to automatically respond to cyber incidents and mitigate potential risks or attacks. However, to launch a successful cyber defense, ACD strategies need to be proven effective in neutralizing the threats and enforceable under the current state and capabilities of the network. In this paper, we present a bounded model checking framework based on SMT to verify that the network can support the given ACD strategies accurately and safely without jeopardizing cyber mission invariants. We abstract the ACD strategies as sets of serializable reconfigurations and provide user interfaces to define cyber mission invariants as reachability, security, and QoS properties. We then verify the satisfaction of these invariants under the given strategies. We implemented this system on OpenFlow-based Software Defined Networks and we evaluated the time complexity for verifying ACD strategies on OpenFlow networks of over two thousand nodes and thousands of rules.

Security configuration analytics using video games

Computing systems today have a large number of security configuration settings that enforce security properties. However, vulnerabilities and incorrect configuration increase the potential for attacks. Provable verification and simulation tools have been introduced to eliminate configuration conflicts and weaknesses, which can increase system robustness against attacks. Most of these tools require special knowledge in formal methods and precise specification for requirements in special languages, in addition to their excessive need for computing resources. Video games have been utilized by researchers to make educational software more attractive and engaging. Publishing these games for crowdsourcing can also stimulate competition between players and increase the game educational value. In this paper we introduce a game interface, called NetMaze, that represents the network configuration verification problem as a video game and allows for attack analysis. We aim to make the security analysis and hardening usable and accurately achievable, using the power of video games and the wisdom of crowdsourcing. Players can easily discover weaknesses in network configuration and investigate new attack scenarios. In addition, the gameplay scenarios can also be used to analyze and learn attack attribution considering human factors. In this paper, we present a provable mapping from the network configuration to 3D game objects.