Identity Management and Authorization Infrastructure in Secure Mobile Access to Electronic Health Records

We live in an age of the mobile paradigm of anytime/anywhere access, as the mobile device is the most ubiquitous device that people now hold. Due to their portability, availability, easy of use, communication, access and sharing of information within various domains and areas of our daily lives, the acceptance and adoption of these devices is still growing. However, due to their potential and raising numbers, mobile devices are a growing target for attackers and, like other technologies, mobile applications are still vulnerable. Health information systems are composed with tools and software to collect, manage, analyze and process medical information (such as electronic health records and personal health records). Therefore, such systems can empower the performance and maintenance of health services, promoting availability, readability, accessibility and data sharing of vital information about a patients overall medical history, between geographic fragmented health services. Quick access to information presents a great importance in the health sector, as it accelerates work processes, resulting in better time utilization. Additionally, it may increase the quality of care. However health information systems store and manage highly sensitive data, which raises serious concerns regarding patients privacy and safety, and may explain the still increasing number of malicious incidents reports within the health domain. Data related to health information systems are highly sensitive and subject to severe legal and regulatory restrictions, that aim to protect the individual rights and privacy of patients. Along side with these legislations, security requirements must be analyzed and measures implemented. Within the necessary security requirements to access health data, secure authentication, identity management and access control are essential to provide adequate means to protect data from unauthorized accesses. However, besides the use of simple authentication models, traditional access control models are commonly based on predefined access policies and roles, and are inflexible. This results in uniform access control decisions through people, different type of devices, environments and situational conditions, and across enterprises, location and time. Although already existent models allow to ensure the needs of the health care systems, they still lack components for dynamicity and privacy protection, which leads to not have desire levels of security and to the patient not to have a full and easy control of his privacy. Within this master thesis, after a deep research and review of the stat of art, was published a novel dynamic access control model, Socio-Technical Risk-Adaptable Access Control modEl (SoTRAACE), which can model the inherent differences and security requirements that are present in this thesis. To do this, SoTRAACE aggregates attributes from various domains to help performing a risk assessment at the moment of the request. The assessment of the risk factors identified in this work is based in a Delphi Study. A set of security experts from various domains were selected, to classify the impact in the risk assessment of each attribute that SoTRAACE aggregates. SoTRAACE was integrated in an architecture with requirements well-founded, and based in the best recommendations and standards (OWASP, NIST 800-53, NIST 800-57), as well based in deep review of the state-of-art. The architecture is further targeted with the essential security analysis and the threat model. As proof of concept, the proposed access control model was implemented within the user-centric architecture, with two mobile prototypes for several types of accesses by patients and healthcare professionals, as well the web servers that handles the access requests, authentication and identity management. The proof of concept shows that the model works as expected, with transparency, assuring privacy and data control to the user without impact for user experience and interaction. It is clear that the model can be extended to other industry domains, and new levels of risks or attributes can be added because it is modular. The architecture also works as expected, assuring secure authentication with multifactor, and secure data share/access based in SoTRAACE decisions. The communication channel that SoTRAACE uses was also protected with a digital certificate. At last, the architecture was tested within different Android versions, tested with static and dynamic analysis and with tests with security tools. Future work includes the integration of health data standards and evaluating the proposed system by collecting users’ opinion after releasing the system to real world.Hoje em dia vivemos em um paradigma móvel de acesso em qualquer lugar/hora, sendo que os dispositivos móveis são a tecnologia mais presente no dia a dia da sociedade. Devido à sua portabilidade, disponibilidade, fácil manuseamento, poder de comunicação, acesso e partilha de informação referentes a várias áreas e domínios das nossas vidas, a aceitação e integração destes dispositivos é cada vez maior. No entanto, devido ao seu potencial e aumento do número de utilizadores, os dispositivos móveis são cada vez mais alvos de ataques, e tal como outras tecnologias, aplicações móveis continuam a ser vulneráveis. Sistemas de informação de saúde são compostos por ferramentas e softwares que permitem recolher, administrar, analisar e processar informação médica (tais como documentos de saúde eletrónicos). Portanto, tais sistemas podem potencializar a performance e a manutenção dos serviços de saúde, promovendo assim a disponibilidade, acessibilidade e a partilha de dados vitais referentes ao registro médico geral dos pacientes, entre serviços e instituições que estão geograficamente fragmentadas. O rápido acesso a informações médicas apresenta uma grande importância para o setor da saúde, dado que acelera os processos de trabalho, resultando assim numa melhor eficiência na utilização do tempo e recursos. Consequentemente haverá uma melhor qualidade de tratamento. Porém os sistemas de informação de saúde armazenam e manuseiam dados bastantes sensíveis, o que levanta sérias preocupações referentes à privacidade e segurança do paciente. Assim se explica o aumento de incidentes maliciosos dentro do domínio da saúde. Os dados de saúde são altamente sensíveis e são sujeitos a severas leis e restrições regulamentares, que pretendem assegurar a proteção dos direitos e privacidade dos pacientes, salvaguardando os seus dados de saúde. Juntamente com estas legislações, requerimentos de segurança devem ser analisados e medidas implementadas. Dentro dos requerimentos necessários para aceder aos dados de saúde, uma autenticação segura, gestão de identidade e controlos de acesso são essenciais para fornecer meios adequados para a proteção de dados contra acessos não autorizados. No entanto, além do uso de modelos simples de autenticação, os modelos tradicionais de controlo de acesso são normalmente baseados em políticas de acesso e cargos pré-definidos, e são inflexíveis. Isto resulta em decisões de controlo de acesso uniformes para diferentes pessoas, tipos de dispositivo, ambientes e condições situacionais, empresas, localizações e diferentes alturas no tempo. Apesar dos modelos existentes permitirem assegurar algumas necessidades dos sistemas de saúde, ainda há escassez de componentes para accesso dinâmico e proteção de privacidade , o que resultam em níveis de segurança não satisfatórios e em o paciente não ter controlo directo e total sobre a sua privacidade e documentos de saúde. Dentro desta tese de mestrado, depois da investigação e revisão intensiva do estado da arte, foi publicado um modelo inovador de controlo de acesso, chamado SoTRAACE, que molda as diferenças de acesso inerentes e requerimentos de segurança presentes nesta tese. Para isto, o SoTRAACE agrega atributos de vários ambientes e domínios que ajudam a executar uma avaliação de riscos, no momento em que os dados são requisitados. A avaliação dos fatores de risco identificados neste trabalho são baseados num estudo de Delphi. Um conjunto de peritos de segurança de vários domínios industriais foram selecionados, para classificar o impacto de cada atributo que o SoTRAACE agrega. O SoTRAACE foi integrado numa arquitectura para acesso a dados médicos, com requerimentos bem fundados, baseados nas melhores normas e recomendações (OWASP, NIST 800-53, NIST 800-57), e em revisões intensivas do estado da arte. Esta arquitectura é posteriormente alvo de uma análise de segurança e modelos de ataque. Como prova deste conceito, o modelo de controlo de acesso proposto é implementado juntamente com uma arquitetura focada no utilizador, com dois protótipos para aplicações móveis, que providênciam vários tipos de acesso de pacientes e profissionais de saúde. A arquitetura é constituída também por servidores web que tratam da gestão de dados, controlo de acesso e autenticação e gestão de identidade. O resultado final mostra que o modelo funciona como esperado, com transparência, assegurando a privacidade e o controlo de dados para o utilizador, sem ter impacto na sua interação e experiência. Consequentemente este modelo pode-se extender para outros setores industriais, e novos níveis de risco ou atributos podem ser adicionados a este mesmo, por ser modular. A arquitetura também funciona como esperado, assegurando uma autenticação segura com multi-fator, acesso e partilha de dados segura baseado em decisões do SoTRAACE. O canal de comunicação que o SoTRAACE usa foi também protegido com um certificado digital. A arquitectura foi testada em diferentes versões de Android, e foi alvo de análise estática, dinâmica e testes com ferramentas de segurança. Para trabalho futuro está planeado a integração de normas de dados de saúde e a avaliação do sistema proposto, através da recolha de opiniões de utilizadores no mundo real

Adding Privacy Protection to Policy Based Authorisation Systems

An authorisation system determines who is authorised to do what i.e. it assigns privileges to users and provides a decision on whether someone is allowed to perform a requested action on a resource. A traditional authorisation decision system, which is simply called authorisation system or system in the rest of the thesis, provides the decision based on a policy which is usually written by the system administrator. Such a traditional authorisation system is not sufficient to protect privacy of personal data, since users (the data subjects) are usually given a take it or leave it choice to accept the controlling organisation’s policy. Privacy is the ability of the owners or subjects of personal data to control the flow of data about themselves, according to their own preferences. This thesis describes the design of an authorisation system that will provide privacy for personal data by including sticky authorisation policies from the issuers and data subjects, to supplement the authorisation policy of the controlling organisation. As personal data moves from controlling system to controlling system, the sticky policies travel with the data. A number of data protection laws and regulations have been formulated to protect the privacy of individuals. The rights and prohibitions provided by the law need to be enforced by the authorisation system. Hence, the designed authorisation system also includes the authorisation rules from the legislation. This thesis describes the conversion of rules from the EU Data Protection Directive into machine executable rules. Due to the nature of the legislative rules, not all of them could be converted into deterministic machine executable rules, as in several cases human intervention or human judgement is required. This is catered for by allowing the machine rules to be configurable. Since the system includes independent policies from various authorities (law, issuer, data subject and controller) conflicts may arise among the decisions provided by them. Consequently, this thesis describes a dynamic, automated conflict resolution mechanism. Different conflict resolution algorithms are chosen based on the request contexts. As the EU Data Protection Directive allows processing of personal data based on contracts, we designed and implemented a component, Contract Validation Service (ConVS) that can validate an XML based digital contract to allow processing of personal data based on a contract. The authorisation system has been implemented as a web service and the performance of the system is measured, by first deploying it in a single computer and then in a cloud server. Finally the validity of the design and implementation are tested against a number of use cases based on scenarios involving accessing medical data in a health service provider’s system and accessing personal data such as CVs and degree certificates in an employment service provider’s system. The machine computed authorisation decisions are compared to the theoretical decisions to ensure that the system returns the correct decisions

Organisational and cross-organisational identity management

We are all familiar with the overwhelming number of usernames and passwords needed in our daily life in the networked world. Services need to identify their end users and keep record on them. Traditionally, this has been done by providing the end user with an extra username and password for each new service. Managing all these isolated user identities is painful for the end user and work-intensive for the service owner. Having out-of-date user accounts and privileges is also a security threat for an organisation. Identity management refers to the process of representing and recognising entities as digital identities in computer networks. In an organisation, an end user s identity has a lifecycle. An identity is created when the user enters the organisation; for example, a new employee is hired, a student is admitted in a school or a company gets a new customer. Changes in the end user s affiliation to the organisation are reflected to his identity, and when the end user departs, his identity needs to be revoked. Organisational identity management develops and maintains an architecture that supports maintenance of user identities during their life cycle. In crossorganisational identity management, these identities are used also when accessing services that are outside the organisation. This thesis studies identity management in organisational and cross-organisational services. An organisation s motivations for improving identity management are presented. Attention is paid to how the person registries in an organisation should be interconnected to introduce an aggregated view on an end user s identity. Connection between identity management and introduction of more reliable authentication methods is shown. The author suggests what needs to be taken into account in a usable deployment of single sign-on and PKI for authentication. Federated identity management is a new way to implement end user identity management in services that cross organisational boundaries. This thesis studies how to establish a federation, an association of organisations that wants to exchange information about their users and services to enable cross-organisational collaborations and transactions. The author presents guidelines for organising a federation and preserving an end user s privacy in it. Finally, common use scenarios for federated identity management are presented