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Hello, won't you tell me your name?: Investigating Anonymity Abuse in IPFS
Authors:
Christos Karapapas,
Iakovos Pittaras,
George C. Polyzos,
Constantinos Patsakis
Abstract:
The InterPlanetary File System~(IPFS) offers a decentralized approach to file storage and sharing, promising resilience and efficiency while also realizing the Web3 paradigm. Simultaneously, the offered anonymity raises significant questions about potential misuse. In this study, we explore methods that malicious actors can exploit IPFS to upload and disseminate harmful content while remaining ano…
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The InterPlanetary File System~(IPFS) offers a decentralized approach to file storage and sharing, promising resilience and efficiency while also realizing the Web3 paradigm. Simultaneously, the offered anonymity raises significant questions about potential misuse. In this study, we explore methods that malicious actors can exploit IPFS to upload and disseminate harmful content while remaining anonymous. We evaluate the role of pinning services and public gateways, identifying their capabilities and limitations in maintaining content availability. Using scripts, we systematically test the behavior of these services by uploading malicious files. Our analysis reveals that pinning services and public gateways lack mechanisms to assess or restrict the propagation of malicious content.
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Submitted 4 June, 2025;
originally announced June 2025.
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Authentication, Authorization, and Selective Disclosure for IoT data sharing using Verifiable Credentials and Zero-Knowledge Proofs
Authors:
Nikos Fotiou,
Iakovos Pittaras,
Spiros Chadoulos,
Vasilios A. Siris,
George C. Polyzos,
Nikolaos Ipiotis,
Stratos Keranidis
Abstract:
As IoT becomes omnipresent vast amounts of data are generated, which can be used for building innovative applications. However,interoperability issues and security concerns, prevent harvesting the full potentials of these data. In this paper we consider the use case of data generated by smart buildings. Buildings are becoming ever "smarter" by integrating IoT devices that improve comfort through s…
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As IoT becomes omnipresent vast amounts of data are generated, which can be used for building innovative applications. However,interoperability issues and security concerns, prevent harvesting the full potentials of these data. In this paper we consider the use case of data generated by smart buildings. Buildings are becoming ever "smarter" by integrating IoT devices that improve comfort through sensing and automation. However, these devices and their data are usually siloed in specific applications or manufacturers, even though they can be valuable for various interested stakeholders who provide different types of "over the top" services, e.g., energy management. Most data sharing techniques follow an "all or nothing" approach, creating significant security and privacy threats, when even partially revealed, privacy-preserving, data subsets can fuel innovative applications. With these in mind we develop a platform that enables controlled, privacy-preserving sharing of data items. Our system innovates in two directions: Firstly, it provides a framework for allowing discovery and selective disclosure of IoT data without violating their integrity. Secondly, it provides a user-friendly, intuitive mechanisms allowing efficient, fine-grained access control over the shared data. Our solution leverages recent advances in the areas of Self-Sovereign Identities, Verifiable Credentials, and Zero-Knowledge Proofs, and it integrates them in a platform that combines the industry-standard authorization framework OAuth 2.0 and the Web of Things specifications.
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Submitted 1 September, 2022;
originally announced September 2022.
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Ransomware as a Service using Smart Contracts and IPFS
Authors:
Christos Karapapas,
Iakovos Pittaras,
Nikos Fotiou,
George C. Polyzos
Abstract:
Decentralized systems, such as distributed ledgers and the InterPlanetary File System (IPFS), are designed to offer more open and robust services. However, they also create opportunities for illegal activities. We demonstrate how these technologies can be used to launch a ransomware as a service campaign. We show that criminals can transact with affiliates and victims without having to reveal thei…
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Decentralized systems, such as distributed ledgers and the InterPlanetary File System (IPFS), are designed to offer more open and robust services. However, they also create opportunities for illegal activities. We demonstrate how these technologies can be used to launch a ransomware as a service campaign. We show that criminals can transact with affiliates and victims without having to reveal their identity. Furthermore, by exploiting the robustness and resilience to churn of IPFS, as well as the decentralized computing capabilities of Ethereum, criminals can remain offline during most procedures, with many privacy guarantees.
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Submitted 9 March, 2020;
originally announced March 2020.
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OAuth 2.0 authorization using blockchain-based tokens
Authors:
Nikos Fotiou,
Iakovos Pittaras,
Vasilios A. Siris,
Spyros Voulgaris,
George C. Polyzos
Abstract:
OAuth 2.0 is the industry-standard protocol for authorization. It facilitates secure service provisioning, as well as secure interoperability among diverse stakeholders. All OAuth 2.0 protocol flows result in the creation of an access token, which is then used by a user to request access to a protected resource. Nevertheless, the definition of access tokens is transparent to the OAuth 2.0 protocol…
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OAuth 2.0 is the industry-standard protocol for authorization. It facilitates secure service provisioning, as well as secure interoperability among diverse stakeholders. All OAuth 2.0 protocol flows result in the creation of an access token, which is then used by a user to request access to a protected resource. Nevertheless, the definition of access tokens is transparent to the OAuth 2.0 protocol, which does not specify any particular token format, how tokens are generated, or how they are used. Instead, the OAuth 2.0 specification leaves all these as design choices for integrators. In this paper, we propose a new type of OAuth 2.0 token backed by a distributed ledger. Our construction is secure, and it supports proof-of-possession, auditing, and accountability. Furthermore, we provide added-value token management services, including revocation, delegation, and fair exchange by leveraging smart contracts. We realized a proof-of-concept implementation of our solution using Ethereum smart contracts and the ERC-721 token specification.
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Submitted 28 January, 2020;
originally announced January 2020.
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Enabling Opportunistic Users in Multi-Tenant IoT Systems using Decentralized Identifiers and Permissioned Blockchains
Authors:
Nikos Fotiou,
Iakovos Pittaras,
Vasilios A. Siris,
George C. Polyzos
Abstract:
In this work, we leverage advances in decentralized identifiers and permissioned blockchains to build a flexible user authentication and authorization mechanism that offers enhanced privacy, achieves fast revocation, and supports distributed "policy decision points" executed in mutually untrusted entities. The proposed solution can be applied in multi-tenant "IoT hubs" that interconnect diverse Io…
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In this work, we leverage advances in decentralized identifiers and permissioned blockchains to build a flexible user authentication and authorization mechanism that offers enhanced privacy, achieves fast revocation, and supports distributed "policy decision points" executed in mutually untrusted entities. The proposed solution can be applied in multi-tenant "IoT hubs" that interconnect diverse IoT silos and enable authorization of "guest" users, i.e., opportunistic users that have no trust relationship with the system, which has not encountered or known them before.
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Submitted 13 November, 2019;
originally announced November 2019.
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Secure IoT access at scale using blockchains and smart contracts
Authors:
Nikos Fotiou,
Iakovos Pittaras,
Vasilios A. Siris,
Spyros Voulgaris,
George C. Polyzos
Abstract:
Blockchains and smart contracts are an emerging, promising technology, that has received considerable attention. We use the blockchain technology, and in particular Ethereum, to implement a large-scale event-based Internet of Things (IoT) control system. We argue that the distributed nature of the "ledger," as well as, Ethereum's capability of parallel execution of replicated "smart contracts", pr…
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Blockchains and smart contracts are an emerging, promising technology, that has received considerable attention. We use the blockchain technology, and in particular Ethereum, to implement a large-scale event-based Internet of Things (IoT) control system. We argue that the distributed nature of the "ledger," as well as, Ethereum's capability of parallel execution of replicated "smart contracts", provide the sought after automation, generality, flexibility, resilience, and high availability. We design a realistic blockchain-based IoT architecture, using existing technologies while by taking into consideration the characteristics and limitations of IoT devices and applications. Furthermore, we leverage blockchain's immutability and Ethereum's support for custom tokens to build a robust and efficient token-based access control mechanism. Our evaluation shows that our solution is viable and offers significant security and usability advantages.
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Submitted 8 July, 2019;
originally announced July 2019.