Biblio

OAuth 2.0 is one of the most widely used Internet protocols for authorization/single sign-on (SSO) and is also the foundation of the new SSO protocol OpenID Connect. Due to its complexity and its flexibility, it is difficult to comprehensively analyze the security of the OAuth 2.0 standard, yet it is critical to obtain practical security guarantees for OAuth 2.0. In this paper, we present the first computationally sound security analysis of OAuth 2.0. First, we introduce a new primitive, the three-party authenticated secret distribution (3P-ASD for short) protocol, which plays the role of issuing the secret and captures the token issue process of OAuth 2.0. As far as we know, this is the first attempt to formally abstract the authorization technology into a general primitive and then define its security. Then, we present a sufficiently rich three-party security model for OAuth protocols, covering all kinds of authorization flows, providing reasonably strong security guarantees and moreover capturing various web features. To confirm the soundness of our model, we also identify the known attacks against OAuth 2.0 in the model. Furthermore, we prove that two main modes of OAuth 2.0 can achieve our desired security by abstracting the token issue process into a 3P-ASD protocol. Our analysis is not only modular which can reflect the compositional nature of OAuth 2.0, but also fine-grained which can evaluate how the intermediate parameters affect the final security of OAuth 2.0.

Forced by regulations and industry demand, banks worldwide are working to open their customers' online banking accounts to third-party services via web-based APIs. By using these so-called Open Banking APIs, third-party companies, such as FinTechs, are able to read information about and initiate payments from their users' bank accounts. Such access to financial data and resources needs to meet particularly high security requirements to protect customers. One of the most promising standards in this segment is the OpenID Financial-grade API (FAPI), currently under development in an open process by the OpenID Foundation and backed by large industry partners. The FAPI is a profile of OAuth 2.0 designed for high-risk scenarios and aiming to be secure against very strong attackers. To achieve this level of security, the FAPI employs a range of mechanisms that have been developed to harden OAuth 2.0, such as Code and Token Binding (including mTLS and OAUTB), JWS Client Assertions, and Proof Key for Code Exchange. In this paper, we perform a rigorous, systematic formal analysis of the security of the FAPI, based on an existing comprehensive model of the web infrastructure - the Web Infrastructure Model (WIM) proposed by Fett, Küsters, and Schmitz. To this end, we first develop a precise model of the FAPI in the WIM, including different profiles for read-only and read-write access, different flows, different types of clients, and different combinations of security features, capturing the complex interactions in a web-based environment. We then use our model of the FAPI to precisely define central security properties. In an attempt to prove these properties, we uncover partly severe attacks, breaking authentication, authorization, and session integrity properties. We develop mitigations against these attacks and finally are able to formally prove the security of a fixed version of the FAPI. Although financial applications are high-stakes environments, this work is the first to formally analyze and, importantly, verify an Open Banking security profile. By itself, this analysis is an important contribution to the development of the FAPI since it helps to define exact security properties and attacker models, and to avoid severe security risks before the first implementations of the standard go live. Of independent interest, we also uncover weaknesses in the aforementioned security mechanisms for hardening OAuth 2.0. We illustrate that these mechanisms do not necessarily achieve the security properties they have been designed for.

The management of security credentials (e.g., passwords, secret keys) for computational science workflows is a burden for scientists and information security officers. Problems with credentials (e.g., expiration, privilege mismatch) cause workflows to fail to fetch needed input data or store valuable scientific results, distracting scientists from their research by requiring them to diagnose the problems, re-run their computations, and wait longer for their results. In this paper, we introduce SciTokens, open source software to help scientists manage their security credentials more reliably and securely. We describe the SciTokens system architecture, design, and implementation addressing use cases from the Laser Interferometer Gravitational-Wave Observatory (LIGO) Scientific Collaboration and the Large Synoptic Survey Telescope (LSST) projects. We also present our integration with widely-used software that supports distributed scientific computing, including HTCondor, CVMFS, and XrootD. SciTokens uses IETF-standard OAuth tokens for capability-based secure access to remote scientific data. The access tokens convey the specific authorizations needed by the workflows, rather than general-purpose authentication impersonation credentials, to address the risks of scientific workflows running on distributed infrastructure including NSF resources (e.g., LIGO Data Grid, Open Science Grid, XSEDE) and public clouds (e.g., Amazon Web Services, Google Cloud, Microsoft Azure). By improving the interoperability and security of scientific workflows, SciTokens 1) enables use of distributed computing for scientific domains that require greater data protection and 2) enables use of more widely distributed computing resources by reducing the risk of credential abuse on remote systems.

Identities are known as the most sensitive information. With the increasing number of connected objects and identities (a connected object may have one or many identities), the computing and communication capabilities improved to manage these connected devices and meet the needs of this progress. Therefore, new IoT Identity Management System (IDMS) requirements have been introduced. In this work, we suggest an IDMS approach to protect private information and ensures domain change in IoT for mobile clients using a personal authentication device. Firstly, we present basic concepts, existing requirements and limits of related works. We also propose new requirements and show our motivations. Next, we describe our proposal. Finally, we give our security approach validation, perspectives, and some concluding remarks.

Enterprises have recognised the importance of personal mobile devices for business and official use. Employees and consumers have been freely accessing resources and services from their principal organisation and partners' businesses on their mobile devices, to improve the efficiency and productivity of their businesses. This mobile computing-based business model has one major challenge, that of ascertaining and linking users' identities and access rights across business partners. The parent organisation owns all the confidential information about users but the collaborative organisation has to verify users' identities and access rights to allow access to their services and resources. This challenge involves resolving how to communicate users' identities to collaborative organisations without sending their confidential information. Several generic Identity and Access Management (IAM) standards have been proposed, and three have become established standards: Security Assertion Markup Language (SAML), Open Authentication (OAuth), and OpenID Connect (OIDC). Mobile computing and communication have some specific requirements and limitations; therefore, this paper evaluates these IAM standards to ascertain suitable IAM to protect mobile computing and communication. This evaluation is based on the three types of analyses: comparative analysis, suitability analysis and security vulnerability analysis of SAML, OAuth and OIDC.

Access to computer systems and the information held on them, be it commercially or personally sensitive, is naturally, strictly controlled by both legal and technical security measures. One such method is digital identity, which is used to authenticate and authorize users to provide access to IT infrastructure to perform official, financial or sensitive operations within organisations. However, transmitting and sharing this sensitive information with other organisations over insecure channels always poses a significant security and privacy risk. An example of an effective solution to this problem is the Federated Identity Management (FIdM) standard adopted in the cloud environment. The FIdM standard is used to authenticate and authorize users across multiple organisations to obtain access to their networks and resources without transmitting sensitive information to other organisations. Using the same authentication and authorization details among multiple organisations in one federated group, it protects the identities and credentials of users in the group. This protection is a balance, mitigating security risk whilst maintaining a positive experience for users. Three of the most popular FIdM standards are Security Assertion Markup Language (SAML), Open Authentication (OAuth), and OpenID Connect (OIDC). This paper presents an assessment of these standards considering their architectural design, working, security strength and security vulnerability, to cognise and ascertain effective usages to protect digital identities and credentials. Firstly, it explains the architectural design and working of these standards. Secondly, it proposes several assessment criteria and compares functionalities of these standards based on the proposed criteria. Finally, it presents a comprehensive analysis of their security vulnerabilities to aid in selecting an apposite FIdM. This analysis of security vulnerabilities is of great significance because their improper or erroneous deployme- t may be exploited for attacks.

Delegated authorization protocols have become wide-spread to implement Web applications and services, where some popular providers managing people identity information and personal data allow their users to delegate third party Web services to access their data. In this paper, we analyze the risks related to untrusted providers not behaving correctly, and we solve this problem by proposing the first verifiable delegated authorization protocol that allows third party services to verify the correctness of users data returned by the provider. The contribution of the paper is twofold: we show how delegated authorization can be cryptographically enforced through authenticated data structures protocols, we extend the standard OAuth2 protocol by supporting efficient and verifiable delegated authorization including database updates and privileges revocation.

UnlimitID is a method for enhancing the privacy of commodity OAuth and applications such as OpenID Connect, using anonymous attribute-based credentials based on algebraic Message Authentication Codes (aMACs). OAuth is one of the most widely used protocols on the Web, but it exposes each of the requests of a user for data by each relying party (RP) to the identity provider (IdP). Our approach allows for the creation of multiple persistent and unlinkable pseudo-identities and requires no change in the deployed code of relying parties, only in identity providers and the client.

Cloud computing is an emerging paradigm shifting the shape of computing models from being a technology to a utility. However, security, privacy and trust are amongst the issues that can subvert the benefits and hence wide deployment of cloud computing. With the introduction of omnipresent mobile-based clients, the ubiquity of the model increases, suggesting a still higher integration in life. Nonetheless, the security issues rise to a higher degree as well. The constrained input methods for credentials and the vulnerable wireless communication links are among factors giving rise to serious security issues. To strengthen the access control of cloud resources, organizations now commonly acquire Identity Management Systems (IdM). This paper presents that the most popular IdM, namely OAuth, working in scope of Mobile Cloud Computing has many weaknesses in authorization architecture. In particular, authors find two major issues in current IdM. First, if the IdM System is compromised through malicious code, it allows a hacker to get authorization of all the protected resources hosted on a cloud. Second, all the communication links among client, cloud and IdM carries complete authorization token, that can allow hacker, through traffic interception at any communication link, an illegitimate access of protected resources. We also suggest a solution to the reported problems, and justify our arguments with experimentation and mathematical modeling.

One of the challenges in a distributed data infrastructure is how users authenticate to the infrastructure, and how their authorisations are tracked. Each user community comes with its own established practices, all different, and users are put off if they need to use new, difficult tools. From the perspective of the infrastructure project, the level of assurance must be high enough, and it should not be necessary to reimplement an authentication and authorisation infrastructure (AAI). In the EUDAT project, we chose to implement a mostly loosely coupled approach based on the outcome of the Contrail and Unicore projects. We have preferred a practical approach, combining the outcome of several projects who have contributed parts of the puzzle. The present paper aims to describe the experiences with the integration of these parts. Eventually, we aim to have a full framework which will enable us to easily integrate new user communities and new services.

This paper proposes a security architecture for an IoT transparent middleware. Focused on bringing real life objects to the virtual realm, the proposed architecture is deployable and comprises protection measures based on existent technologies for security such as AES, TLS and oAuth. This way, privacy, authenticity, integrity and confidentiality on data exchange services are integrated to provide security for generated smart objects and for involved users and services in a reliable and deployable manner.