Untrusted Domains Research Articles

ZTWeb: Cross site scripting detection based on zero trust

Policy defense technology is the mainstream XSS defense technology. However, defense mechanisms with fixed policies may hardly cover the attack surface persistently in dynamic environments. Moreover, the undifferentiated policy makes the malicious code and developer code have the same resource authorization, which leads to the game between the security and usability of the page. To tackle this problem, we propose a zero trust-based defense model - ZTWeb, which constructs differentiated and dynamic policies to balance the security and usability of the website. Specifically, ZTWeb micro-segments the protect surface code into the trust domain, executing different authorization policies based on the trust level of the code subject. The key of ZTWeb is to break the control risk of static policy authorization and create dynamic trust by continuously evaluating the behavior of untrusted domains. Trust evaluation takes the call sequence of sensitive resources as the judgment element. We associate the parent-child relationship between domains and divide the behavior branches within the domain to construct a complete, accurate, context-containing behavior sequence. Furthermore, the extracted sequence is regarded as a piece of text, and the TextCNN model is introduced to identify XSS attacks. We evaluate ZTWeb using real datasets collected from GitHub. The experimental results show that the model can achieve an accuracy of 99.7%, the overall performance overhead is low, and strong security is maintained without destroying the website's usability.

Flare: A Fast, Secure, and Memory-Efficient Distributed Analytics Framework

As big data processing in the cloud becomes prevalent today, data privacy on such public platforms raises critical concerns. Hardware-based trusted execution environments (TEEs) provide promising and practical platforms for low-cost privacy-preserving data processing. However, using TEEs to enhance the security of data analytics frameworks like Apache Spark involves challenging issues when separating various framework components into trusted and untrusted domains, demanding meticulous considerations for programmability, performance, and security. Based on Intel SGX, we build Flare, a fast, secure, and memory-efficient data analytics framework with a familiar user programming interface and useful functionalities similar to Apache Spark. Flare ensures confidentiality and integrity by keeping sensitive data and computations encrypted and authenticated. It also supports oblivious processing to protect against access pattern side channels. The main innovations of Flare include a novel abstraction paradigm of shadow operators and shadow tasks to minimize trusted components and reduce domain switch overheads, memory-efficient data processing with proper granularities for different operators, and adaptive parallelization based on memory allocation intensity for better scalability. Flare outperforms the state-of-the-art secure framework by 3.0× to 176.1×, and is also 2.8× to 28.3× faster than a monolithic libOS-based integration approach.

Research on a Dynamic Trusted Model Based on Time-sharing Control

In this paper, a high-availability time-sharing dynamic trusted model is proposed, which controls the access of untrusted domains to trusted domains by time-sharing, dynamically adjusts the trusted domain and untrusted domains, and proves their security with non-interference theory, which improves the usability of the dynamic trusted model.

Building Trusted Federated Learning on Blockchain

Federated learning enables multiple users to collaboratively train a global model using the users’ private data on users’ local machines. This way, users are not required to share their training data with other parties, maintaining user privacy; however, the vanilla federated learning proposal is mainly assumed to be run in a trusted environment, while the actual implementation of federated learning is expected to be performed in untrusted domains. This paper aims to use blockchain as a trusted federated learning platform to realize the missing “running on untrusted domain” requirement. First, we investigate vanilla federate learning issues such as client’s low motivation, client dropouts, model poisoning, model stealing, and unauthorized access. From those issues, we design building block solutions such as incentive mechanism, reputation system, peer-reviewed model, commitment hash, and model encryption. We then construct the full-fledged blockchain-based federated learning protocol, including client registration, training, aggregation, and reward distribution. Our evaluations show that the proposed solutions made federated learning more reliable. Moreover, the proposed system can motivate participants to be honest and perform best-effort training to obtain higher rewards while punishing malicious behaviors. Hence, running federated learning in an untrusted environment becomes possible.

TRAQR: Trust aware End-to-End QoS routing in multi-domain SDN using Blockchain

Recent advances in today’s Internet introduced huge demand for End-to-End Quality of Service (E2E QoS) assurances for delivering different types of traffic (video, live streaming, and telemedicine), originating from a wide spectrum of applications. Such applications stretch across multiple administrative domains and require fair and robust coordination for E2E QoS provisioning. While the selection of trusted domains is of paramount importance for the successful realization of E2E QoS, the issue of domain’s trust while finding E2E QoS paths has not been actively explored in the existing works. Trust awareness reduces the risk of violating QoS and improves the confidence of operating QoS across multiple domains. However, identifying trusted domains, finding the source of trust, and quantifying trust are the major challenges for enabling trust aware E2E QoS routing. Auditability of QoS implementation results at each domain forms a vital source for verifying QoS compliance and subsequently evaluating the trust of the domain. However, securely obtaining logs from the domains and identifying the accountability of domains for E2E QoS, without relying on a third party introduces significant difficulty when evaluating domain trust with respect to QoS compliance. This work proposes Trust aware E2E QoS Routing (TRAQR) framework for provisioning E2E QoS with trust and verifying the QoS compliance in Multi-Domain Software Defined Networks (MD-SDN). TRAQR efficiently leverages the tamper-proof and decentralized properties of Blockchain to store and exchange different kinds of trust information required to provision and verify E2E QoS compliance of the domains. This work developed a proof of concept implementation of the TRAQR in an MD-SDN environment emulated using Mininet, RYU SDN controller, Ethereum Blockchain and Smart Contracts to demonstrate the performance and benefits of TRAQR. Further, the simulations showed that the domain trust parameter introduced significant improvement in QoS compliance, even in the presence of untrusted domains.

On Australia’s Cyber and Critical Technology International Engagement Strategy Towards 6G

In response to the call by the Australian Department of Foreign Affairs and Trade for submissions on the development of Australia’s Cyber and Critical Technology International Engagement Strategy, this paper reviews the most critical technologies; related risks and opportunities; best practices, policies and security frameworks in other countries; relevant government, industry, civil society and academia cooperation initiatives; and proposes how Australia may became a leader in the global Cyberspace. To realise this vision, Australia should play a major role among selected international organizations; support the continuous evolution of critical technologies; adopt a proper technology security assurance scheme; and enforce a certification and accreditation process – against a predetermined set of appropriate security standards and policies – for security authorisation in Australia. This could be achieved with the formulation and implementation of an Australia’s defence-in-depth strategy, augmented by a Zero-Trust model, which enhances security for untrusted domains, and within trusted domains, and meets the baseline requirements of cyber security for the Internet of Things.

Adapting ATLAS@Home to trusted and semi-trusted resources

ATLAS@Home is a volunteer computing project which enables members of the public to contribute computing power to run simulations of the ATLAS experiment at CERN’s Large Hadron Collider. The computing resources provided to ATLAS@Home increasingly come not only from traditional volunteers, but also from data centres or office computers at institutes associated to ATLAS. The design of ATLAS@Home was built around not giving out sensitive credentials to volunteers, which means that a sandbox is needed to bridge data transfers between trusted and untrusted domains. As the scale of ATLAS@Home increases, this sandbox becomes a potential data management bottleneck. This paper explores solutions to this problem based on relaxing the constraints of sending credentials to trusted volunteers, allowing direct data transfer to grid storage and avoiding the intermediate sandbox. Fully trusted resources such as grid worker nodes can run with full access to grid storage, whereas semi-trusted resources such as student desktops can be provided with “macaroons”: time-limited access tokens which can only be used for specific files. The steps towards implementing these solutions as well as initial results with real ATLAS simulation tasks are discussed along with the experience gained so far and the next steps in the project.

Formula: see text]: Oblivious similarity based searching for encrypted data outsourced to an untrusted domain.

Public cloud storage services are becoming prevalent and myriad data sharing, archiving and collaborative services have emerged which harness the pay-as-you-go business model of public cloud. To ensure privacy and confidentiality often encrypted data is outsourced to such services, which further complicates the process of accessing relevant data by using search queries. Search over encrypted data schemes solve this problem by exploiting cryptographic primitives and secure indexing to identify outsourced data that satisfy the search criteria. Almost all of these schemes rely on exact matching between the encrypted data and search criteria. A few schemes which extend the notion of exact matching to similarity based search, lack realism as those schemes rely on trusted third parties or due to increase storage and computational complexity. In this paper we propose Oblivious Similarity based Search () for encrypted data. It enables authorized users to model their own encrypted search queries which are resilient to typographical errors. Unlike conventional methodologies, ranks the search results by using similarity measure offering a better search experience than exact matching. It utilizes encrypted bloom filter and probabilistic homomorphic encryption to enable authorized users to access relevant data without revealing results of search query evaluation process to the untrusted cloud service provider. Encrypted bloom filter based search enables to reduce search space to potentially relevant encrypted data avoiding unnecessary computation on public cloud. The efficacy of is evaluated on Google App Engine for various bloom filter lengths on different cloud configurations.

Privacy-Aware Relevant Data Access with Semantically Enriched Search Queries for Untrusted Cloud Storage Services.

Privacy-aware search of outsourced data ensures relevant data access in the untrusted domain of a public cloud service provider. Subscriber of a public cloud storage service can determine the presence or absence of a particular keyword by submitting search query in the form of a trapdoor. However, these trapdoor-based search queries are limited in functionality and cannot be used to identify secure outsourced data which contains semantically equivalent information. In addition, trapdoor-based methodologies are confined to pre-defined trapdoors and prevent subscribers from searching outsourced data with arbitrarily defined search criteria. To solve the problem of relevant data access, we have proposed an index-based privacy-aware search methodology that ensures semantic retrieval of data from an untrusted domain. This method ensures oblivious execution of a search query and leverages authorized subscribers to model conjunctive search queries without relying on predefined trapdoors. A security analysis of our proposed methodology shows that, in a conspired attack, unauthorized subscribers and untrusted cloud service providers cannot deduce any information that can lead to the potential loss of data privacy. A computational time analysis on commodity hardware demonstrates that our proposed methodology requires moderate computational resources to model a privacy-aware search query and for its oblivious evaluation on a cloud service provider.

Design and Implementation of Efficient Integrity Protection for Open Mobile Platforms

The security of mobile devices such as cellular phones and smartphones has gained extensive attention due to their increasing usage in people's daily life. The problem is challenging as the computing environments of these devices have become more open and general-purpose while at the same time they have the constraints of performance and user experience. We propose and implement SEIP, a simple and efficient but yet effective solution for the integrity protection of real-world cellular phone platforms, which is motivated by the disadvantages of applying traditional integrity models on these performance and user experience constrained devices. The major security objective of SEIP is to protect trusted services and resources (e.g., those belonging to cellular service providers and device manufacturers) from third-party code. We propose a set of simple integrity protection rules based upon open mobile operating system environments and application behaviors. Our design leverages the unique features of mobile devices, such as service convergence and limited permissions of user installed applications, and easily identifies the borderline between trusted and untrusted domains on mobile platforms. Our approach, thus, significantly simplifies policy specifications while still achieves a high assurance of platform integrity. SEIP is deployed within a commercially available Linux-based smartphone and demonstrates that it can effectively prevent certain malware. The security policy of our implementation is less than 20 kB, and a performance study shows that it is lightweight.

PrivaSIP: Ad-hoc identity privacy in SIP

In modern and future networks that belong to different providers, multimedia protocols will have to operate through multiple domains. In such an environment security is considered a crucial parameter; this is true especially for privacy since not all domains can be considered trusted beforehand in terms of personal data protection. Probably the most promising protocol for multimedia session management is SIP. While SIP is popular and a lot of research has been conducted, it still has some security issues, one of which is related to privacy and more particularly the protection of user identities (IDs). In the general case everybody can reveal the communicating parties IDs by simply eavesdropping on the exchanged SIP messages. In this paper we analyze the lack of user ID protection in SIP and propose two solutions; in the first the ID of the caller is protected while in the second both IDs of the caller and the callee are protected. Our work also includes performance results and extensive comparison with similar methods. The most significant advantage of our method is that it can assure user ID protection even when SIP messages are transmitted through untrusted SIP domains before reaching the Home Domain of the user or another trusted domain. Moreover, it does not require from the SIP Proxy server to maintain state information for exchanged SIP requests and respective responses.

An interoperability system for authentication and authorisation in VANETs

Vehicular ad hoc networks (VANETs) have evolved considerably over the last years, but despite the wide number of potential applications, VANETs also raise a broad range of critical security and privacy challenges. To achieve privacy, VANETs enforce the concepts of authentication and authorisation via public key infrastructures, relying on a large set of regional certification authorities with explicit cross-certification agreements to provide interoperability for vehicles and services. To avoid the burden of managing these cross-certificates, our research proposes the interoperability system (IS), an architecture to provide VANETs' nodes with a security mechanism for mutually untrusted domains. The IS supplies vehicles with a trusted set of credentials by implementing a certificate status service and a security level evaluator. This paper shows that the proposed architecture can be used to implement a mandatory access control mechanism in two VANET scenarios with a protocol independent of the underlying communication system.

Trusting third-party storage providers for holding personal information. A context-based approach to protect identity-related data in untrusted domains

The never ending growth of digital information and the availability of low-cost storage facilities and networks capacity is leading users towards moving their data to remote storage resources. Since users’ data often holds identity-related information, several privacy issues arise when data can be stored in untrusted domains. In addition digital identity management is becoming extremely complicated due to the identity replicas proliferation necessary to get authentication in different domains. GMail and Amazon Web Services, for instance, are two examples of online services adopted by million of users throughout the world which hold huge amounts of sensitive users data. State-of-the-art encryption tools for large-scale distributed infrastructures allow users to encrypt content locally before storing it on a remote untrusted repository. This approach can experience performance drawbacks, when very large data-sets must be encrypted/decrypted on a single machine. The proposed approach extends the existing solutions by providing two additional features: (1) the encryption can also be delegated to a pool of remote trusted computing resources, and (2) the definition of the encryption context which drives the tool to select the best strategy to process the data. The performance benchmarks are based on the results of tests carried out both on a local workstation and on the Grid INFN Laboratory for Dissemination Activities (GILDA) testbed.

Conformance Testing a Set of Criteria for Assessing Trust

The ability to authenticate the identity of an entity in an open and insecure environment such as the Internet plays an important role in reducing potential threats and Public key Infrastructure techniques assist in verifying the identity of entities participating in online transactions. A Certification Authority (CA) issues certificates to entities and vouches for the identity embodied in them. These certificates inherit their trustworthiness from the fact that their issuer is a known (trusted) CA. We have developed criteria for authenticating an entity’s identity when there is no trusted CA (untrusted domain ) to vouch for the trust embodied in a certificate. This paper describes conformance testing of the criteria we developed; the ultimate objective of this being to show their efficiency and robustness.

Confidential mobile mail retrieval

The method of probalistic searching on encrypted data can be utilized for a confidential mobile mail retrieval system where the e-mails are stored and processed in an untrusted domain. We discuss the necessary modification to the theoretical settings in the procedures and algorithms, but also the actual used technical means. We show that it is possible to deploy an adapted version of the system in [Proceedings of the 21st Institute of Electrical and Electronics Engineers Inc. (IEEE) Symposium on Security and Privacy, Berkeley, CA (2000) 44] in a secure and user-friendly manner in the constraint mobile environment.